OK. I've long used this site as a reference, but I've now hit a wall of my own.
I am creating a custom server control which inherits from the System.Web.UI.WebControls.GridView class. It's purpose is simply to display a grid with a very defined format. It binds and loads the data fine, but trying to activate any of the paging throws an exception saying "Multiple controls with the same ID 'lblHdrText_2' were found. FindControl requires that controls have unique IDs.".
I could just throw the event out to the user and let them do the paging, but one of the goals was to have this control be able to handle its own paging, just like the GridView control already does.
I'm having the same problem for sorting and altering the page size as well. Basically anytime I call "DataBind" within the control after it has already been rendered.
Here's the code to handle those events:
protected void OnFirstPageClicked(EventArgs e)
{
if (this.FirstPageClicked != null)
this.FirstPageClicked.Invoke(this, e);
GridViewPageEventArgs pgea = new GridViewPageEventArgs(0);
this.OnPageIndexChanging(pgea);
if (pgea.Cancel)
return;
this.PageIndex = 0;
this.RefreshData();
this.OnPageIndexChanged(e);
}
protected void OnLastPageClicked(EventArgs e)
{
if (this.LastPageClicked != null)
this.LastPageClicked.Invoke(this, e);
GridViewPageEventArgs pgea = new GridViewPageEventArgs(this.PageCount - 1);
this.OnPageIndexChanging(pgea);
if (pgea.Cancel)
return;
this.PageIndex = this.PageCount - 1;
this.RefreshData();
this.OnPageIndexChanged(e);
}
protected void OnPreviousPageClicked(EventArgs e)
{
if (this.PageIndex > 0)
{
if (this.PreviousPageClicked != null)
this.PreviousPageClicked.Invoke(this, e);
GridViewPageEventArgs pgea = new GridViewPageEventArgs(this.PageIndex++);
this.OnPageIndexChanging(pgea);
if (pgea.Cancel)
return;
this.PageIndex--;
this.RefreshData();
this.OnPageIndexChanged(e);
}
}
protected void OnNextPageClicked(EventArgs e)
{
if (this.PageIndex < this.PageCount - 1)
{
if (this.NextPageClicked != null)
this.NextPageClicked.Invoke(this, e);
GridViewPageEventArgs pgea = new GridViewPageEventArgs(this.PageIndex++);
this.OnPageIndexChanging(pgea);
if (pgea.Cancel)
return;
this.PageIndex++;
this.RefreshData();
this.OnPageIndexChanged(e);
}
}
protected void OnPageSizeChanged(EventArgs e)
{
this.RefreshData();
if (this.PageSizeChanged != null)
this.PageSizeChanged.Invoke(this, e);
}
protected override void OnDataBound(EventArgs e)
{
base.OnDataBound(e);
}
private void RefreshData()
{
this.DataBind();
}
private void imgPg_OnCommand(object sender, CommandEventArgs e)
{
switch (e.CommandName)
{
case "FirstPage":
this.OnFirstPageClicked(EventArgs.Empty);
break;
case "LastPage":
this.OnLastPageClicked(EventArgs.Empty);
break;
case "PrevPage":
this.OnPreviousPageClicked(EventArgs.Empty);
break;
case "NextPage":
this.OnNextPageClicked(EventArgs.Empty);
break;
}
}
private void drpPageSz_SelectedIndexChanged(object sender, EventArgs e)
{
DropDownList drpPgSz = (sender as DropDownList);
if (drpPgSz != null)
{
this.PageSize = int.Parse(drpPgSz.SelectedValue);
this.OnPageSizeChanged(e);
}
else
throw new Exception("Unable to determine page size: cannot cast sender as DropDownList.");
}
The actual event handlers are at the bottom. The "RefreshData" method is just there because I was experimenting with different ways of clearing the controls from the grid before I called "DataBind". So far, everything I've tried results in the entire grid not rendering after postback.
I am doing quite a bit with the Render and CreateChildControls, but the header generation itself is completely internal to the System.Web.UI.WebControls.GridView control. Here's my rendering code, if it helps at all:
protected override void OnPreRender(EventArgs e)
{
Control link = this.Page.Header.FindControl("CustomGridViewCss");
if (link == null)
{
System.Web.UI.HtmlControls.HtmlLink newLink = new System.Web.UI.HtmlControls.HtmlLink();
newLink.ID = "CustomGridViewCss";
newLink.Attributes.Add("href", this.Page.ClientScript.GetWebResourceUrl(typeof(ITCWebToolkit.Web.UI.Controls.GridView), "ITCWebToolkit.Web.UI.Controls.style.CustomGridView.css"));
newLink.Attributes.Add("type", "text/css");
newLink.Attributes.Add("rel", "stylesheet");
this.Page.Header.Controls.Add(newLink);
}
base.OnPreRender(e);
this.EnsureChildControls();
}
protected override void Render(HtmlTextWriter writer)
{
if (this._imgFPg != null)
this.Page.ClientScript.RegisterForEventValidation(this._imgFPg.UniqueID);
if (this._imgPrevPg != null)
this.Page.ClientScript.RegisterForEventValidation(this._imgPrevPg.UniqueID);
if (this._imgNextPg != null)
this.Page.ClientScript.RegisterForEventValidation(this._imgNextPg.UniqueID);
if (this._imgLastPg != null)
this.Page.ClientScript.RegisterForEventValidation(this._imgLastPg.UniqueID);
if (this._drpPageSz != null)
this.Page.ClientScript.RegisterForEventValidation(this._drpPageSz.UniqueID);
if (this.HeaderRow != null)
for (int i = 1; i < this.HeaderRow.Cells.Count - 2; i++)
if (i < this.Columns.Count && this.Columns[i] is SortableField && ((this.Columns[i] as SortableField).ShowSort))
{
ImageButton img = (this.HeaderRow.Cells[i].FindControl("imgSort_" + i.ToString()) as ImageButton);
if (img != null)
this.Page.ClientScript.RegisterForEventValidation(img.UniqueID);
}
base.Render(writer);
}
protected override Table CreateChildTable()
{
this.PagerSettings.Visible = false;
this.GridLines = GridLines.None;
Table tbl = base.CreateChildTable();
tbl.Attributes.Add("name", this.UniqueID);
return tbl;
}
protected override int CreateChildControls(System.Collections.IEnumerable dataSource, bool dataBinding)
{
this.GridLines = GridLines.None;
int iCount = base.CreateChildControls(dataSource, dataBinding);
// Modify footer row
System.Web.UI.WebControls.GridViewRow ftr = this.FooterRow;
// NOTE: We're modifying the footer first, because we're looking at the
// total number of rows in the header for the ColSpan property we
// use in the footer and we want the row count *before* we modify
// the header.
ftr.Cells.Clear();
this.BuildFooter(this.FooterRow);
// Modify Header Row
System.Web.UI.WebControls.GridViewRow hdr = this.HeaderRow;
hdr.CssClass = "GridViewHeader";
for (int c = 0; c < hdr.Cells.Count; c++)
{
hdr.Cells[c].CssClass = "GridViewHeaderTC";
if (c > 0)
hdr.Cells[c].Style.Add("border-left", "solid 1px #ccccd3");
if (c < this.Columns.Count && this.Columns[c] is SortableField && ((this.Columns[c] as SortableField).ShowSort))
{
hdr.Cells[c].Controls.Clear();
Label lblHdrText = new Label();
lblHdrText.ID = "lblHdrText_" + c.ToString();
lblHdrText.Text = hdr.Cells[c].Text;
hdr.Cells[c].Controls.Add(lblHdrText);
ImageButton imgSort = new ImageButton();
imgSort.ID = "imgSort_" + c.ToString();
imgSort.CssClass = "GridViewHeaderSort";
imgSort.ImageUrl = this.Page.ClientScript.GetWebResourceUrl(typeof(ITCWebToolkit.Web.UI.Controls.GridView), "ITCWebToolkit.Web.UI.Controls.images.gridView.Sort.png");
imgSort.AlternateText = "";
imgSort.CommandArgument = (this.Columns[c] as BoundField).DataField;
imgSort.CommandName = "Sort";
imgSort.Command += new CommandEventHandler(this.imgSort_OnCommand);
hdr.Cells[c].Controls.Add(imgSort);
imgSort.Attributes.Add("name", imgSort.UniqueID);
}
}
TableCell tdTL = new TableCell();
tdTL.Style.Add(HtmlTextWriterStyle.Width, "6px");
tdTL.CssClass = "GridViewHeaderTL";
hdr.Cells.AddAt(0, tdTL);
TableCell tdTR = new TableCell();
tdTR.Style.Add(HtmlTextWriterStyle.Width, "6px");
tdTR.Style.Add("border-left", "1px solid #ccccd3;");
tdTR.CssClass = "GridViewHeaderTR";
hdr.Cells.Add(tdTR);
// Modify individual rows
for (int i = 0; i < this.Rows.Count; i++)
{
System.Web.UI.WebControls.GridViewRow tr = this.Rows[i];
tr.CssClass = (i % 2 == 0) ? "GridViewLineAlt" : "GridViewLine";
for (int c = 0; c < tr.Cells.Count - 1; c++)
tr.Cells[c].Style.Add("border-right", "solid 1px #ccccd3");
TableCell tdL = new TableCell();
tdL.CssClass = "GridViewLineLeft";
tr.Cells.AddAt(0, tdL);
TableCell tdR = new TableCell();
tdR.CssClass = "GridViewLineRight";
tr.Cells.Add(tdR);
}
return iCount;
}
protected void BuildFooter(GridViewRow tr)
{
TableCell tdBL = new TableCell();
tdBL.Style.Add(HtmlTextWriterStyle.Width, "6px");
tdBL.CssClass = "GridViewFooterBL";
tr.Cells.Add(tdBL);
int colCount = this.HeaderRow.Cells.Count;
TableCell td = new TableCell();
td.ID = "tdFooterControls";
td.CssClass = "GridViewFooterBC";
td.ColumnSpan = colCount;
this._spanPgBtns = new Label();
this._spanPgBtns.ID = "spanPgButtons";
this._spanPgBtns.Style.Add("float", "right");
this._spanPgBtns.Style.Add("margin-right", "20px");
this._imgFPg = new ImageButton();
this._imgFPg.ID = "imgFPg";
this._imgFPg.CssClass = "FirstPg";
this._imgFPg.ImageUrl = this.Page.ClientScript.GetWebResourceUrl(typeof(ITCWebToolkit.Web.UI.Controls.GridView), "ITCWebToolkit.Web.UI.Controls.images.gridView.FstPg.png");
this._imgFPg.ImageAlign = ImageAlign.Middle;
this._imgFPg.CommandName = "FirstPage";
this._imgFPg.Command += new CommandEventHandler(this.imgPg_OnCommand);
this._spanPgBtns.Controls.Add(this._imgFPg);
this._imgPrevPg = new ImageButton();
this._imgPrevPg.ID = "imgPrevPg";
this._imgPrevPg.CssClass = "PrevPg";
this._imgPrevPg.ImageUrl = this.Page.ClientScript.GetWebResourceUrl(typeof(ITCWebToolkit.Web.UI.Controls.GridView), "ITCWebToolkit.Web.UI.Controls.images.gridView.PrevPg.png");
this._imgPrevPg.ImageAlign = ImageAlign.Middle;
this._imgPrevPg.CommandName = "PrevPage";
this._imgPrevPg.Command += new CommandEventHandler(this.imgPg_OnCommand);
this._spanPgBtns.Controls.Add(this._imgPrevPg);
Label lblPageNum = new Label();
lblPageNum.ID = "lblPageNum";
lblPageNum.Width = new Unit("50px");
lblPageNum.Text = string.Format("{0} / {1}", this.PageIndex + 1, this.PageCount);
lblPageNum.Style.Add(HtmlTextWriterStyle.TextAlign, "center");
this._spanPgBtns.Controls.Add(lblPageNum);
this._imgNextPg = new ImageButton();
this._imgNextPg.ID = "imgNextPg";
this._imgNextPg.CssClass = "NextPg";
this._imgNextPg.ImageUrl = this.Page.ClientScript.GetWebResourceUrl(typeof(ITCWebToolkit.Web.UI.Controls.GridView), "ITCWebToolkit.Web.UI.Controls.images.gridView.NextPg.png");
this._imgNextPg.ImageAlign = ImageAlign.Middle;
this._imgNextPg.CommandName = "NextPage";
this._imgNextPg.Command += new CommandEventHandler(this.imgPg_OnCommand);
this._spanPgBtns.Controls.Add(this._imgNextPg);
this._imgLastPg = new ImageButton();
this._imgLastPg.ID = "imgLastPg";
this._imgLastPg.CssClass = "LastPg";
this._imgLastPg.ImageUrl = this.Page.ClientScript.GetWebResourceUrl(typeof(ITCWebToolkit.Web.UI.Controls.GridView), "ITCWebToolkit.Web.UI.Controls.images.gridView.LstPg.png");
this._imgLastPg.ImageAlign = ImageAlign.Middle;
this._imgLastPg.CommandName = "LastPage";
this._imgLastPg.Command += new CommandEventHandler(this.imgPg_OnCommand);
this._spanPgBtns.Controls.Add(this._imgLastPg);
td.Controls.Add(this._spanPgBtns);
Label spanPageSz = new Label();
spanPageSz.ID = "spanPageSz";
spanPageSz.Style.Add("margin-left", "20px");
this._drpPageSz = new DropDownList();
this._drpPageSz.ID = "drpPageSzSelect";
this._drpPageSz.AutoPostBack = true;
this._drpPageSz.SelectedIndexChanged += new EventHandler(drpPageSz_SelectedIndexChanged);
this._drpPageSz.Items.Add(new ListItem("10", "10"));
this._drpPageSz.Items.Add(new ListItem("25", "25"));
this._drpPageSz.Items.Add(new ListItem("50", "50"));
this._drpPageSz.Items.Add(new ListItem("100", "100"));
spanPageSz.Controls.Add(this._drpPageSz);
td.Controls.Add(spanPageSz);
Label lblRecVis = new Label();
lblRecVis.ID = "lblRecordsCount";
lblRecVis.Style.Add("margin-left", "20px");
lblRecVis.Text = string.Format("Displaying {0} of {1} records.", Math.Min(this.PageSize, this.Rows.Count - (this.PageIndex * this.PageSize)), this.Rows.Count);
lblRecVis.Text = "Total Record Display";
td.Controls.Add(lblRecVis);
tr.Cells.Add(td);
TableCell tdBR = new TableCell();
tdBR.Style.Add(HtmlTextWriterStyle.Width, "6px");
tdBR.CssClass = "GridViewFooterBR";
tr.Cells.Add(tdBR);
this._imgFPg.Attributes.Add("name", this._imgFPg.UniqueID);
this._imgPrevPg.Attributes.Add("name", this._imgPrevPg.UniqueID);
this._imgNextPg.Attributes.Add("name", this._imgNextPg.UniqueID);
this._imgLastPg.Attributes.Add("name", this._imgLastPg.UniqueID);
this._drpPageSz.Attributes.Add("name", this._drpPageSz.UniqueID);
}
I'm only about 6/10 on custom server controls, so I'm sure there's at least one thing I'm doing wrong here :)
Thanks in advance for any help!
OK. I finally found a reference and answered my own question. The trick is in overriding the "PerformSelect" method and handling DataSource vs DataSourceID there.
Details on how to do this can be found on this MSDN page:
http://msdn.microsoft.com/en-us/library/ms366539(v=vs.90).aspx
Look for the section titled "Initiate Data Retrieval" a little over half-way down.
Related
hi i'm Cannot get value dynamically created textbox and save into database. plz help
his is code which I have created in this code text box are created but when I will input the value in the text and retrieve the value from dynamically created text box it give error
protected void btnAtt_Click(object sender, EventArgs e)
{
int DPLID = int.Parse(DPLCategory.Text);
var query = (from p in database.tbl_Attributes
where p.ProductTypeId_FK == DPLID
select new
{
p.Attribute_Id,
p.AttributeName,
p.ProductTypeId_FK,
}).ToArray();
for (int i = 0; i < query.Count(); i++)
{
Label lblatt = new Label();
lblatt.ID = query[i].AttributeName;
lblatt.Text = query[i].AttributeName + " : ";
lblatt.CssClass = "control-label";
TextBox txtatt = new TextBox();
txtatt.ID = "txtatt"+i;
txtatt.Attributes.Add("runat", "server");
txtatt.Text = String.Empty;
txtatt.CssClass = "form-control input-sm";
HtmlTextWriterTag.Br.ToString();
Place1.Controls.Add(lblatt);
HtmlTextWriterTag.Br.ToString();
Place1.Controls.Add(txtatt);
HtmlTextWriterTag.Br.ToString();
}
}
protected void lbtnSave_Click(object sender, EventArgs e)
{
int DPLID = int.Parse(DPLCategory.Text);
var query = (from p in database.tbl_Attributes
where p.ProductTypeId_FK == DPLID
select new
{
p.Attribute_Id,
p.AttributeName,
p.ProductTypeId_FK,
}).ToArray();
int LastId = database.tbl_Products.Max(p => p.ProductId);
for (int i = 0; i < query.Count(); i++)
{
database.tbl_ProductValue.Add(new Models.tbl_ProductValue()
{
ProductId_FK = LastId,
AttributeID_FK = query[i].Attribute_Id,
ProductValue = ??,
});
database.SaveChanges();
}
}
plz help me for how to get textbox?
I haven't worked with WebForms in a while but you can access the controls by their IDs like this:
ProductValue = ((TextBox)FindControl("txtatt" + i)).Text;
I have this code which generates TextBoxes in a Table dynamically, I got it from a website:
protected void AddStdBtn_Click(object sender, EventArgs e)
{
CreateDynamicTable();
}
private void CreateDynamicTable()
{
// Fetch the number of Rows and Columns for the table
// using the properties
if (ViewState["Stu"] != null)
Students = (DataTable)ViewState["Stu"];
int tblCols = 1;
int tblRows = Int32.Parse(NoTxt.Text);
// Now iterate through the table and add your controls
for (int i = 0; i < tblRows; i++)
{
TableRow tr = new TableRow();
for (int j = 0; j < tblCols; j++)
{
TableCell tc = new TableCell();
TextBox txtBox = new TextBox();
txtBox.ID = "txt-" + i.ToString() + "-" + j.ToString();
txtBox.Text = "RowNo:" + i + " " + "ColumnNo:" + " " + j;
// Add the control to the TableCell
tc.Controls.Add(txtBox);
// Add the TableCell to the TableRow
tr.Cells.Add(tc);
}
// Add the TableRow to the Table
tbl.Rows.Add(tr);
tbl.EnableViewState = true;
ViewState["tbl"] = true;
}
}
protected void CalculateBtn_Click(object sender, EventArgs e)
{
foreach (TableRow tr in tbl.Controls)
{
foreach (TableCell tc in tr.Controls)
{
if (tc.Controls[0] is TextBox)
{
Response.Write(((TextBox)tc.Controls[0]).Text);
}
}
Response.Write("<br/>");
}
}
protected override object SaveViewState()
{
object[] newViewState = new object[2];
List<string> txtValues = new List<string>();
foreach (TableRow row in tbl.Controls)
{
foreach (TableCell cell in row.Controls)
{
if (cell.Controls[0] is TextBox)
{
txtValues.Add(((TextBox)cell.Controls[0]).Text);
}
}
}
newViewState[0] = txtValues.ToArray();
newViewState[1] = base.SaveViewState();
return newViewState;
}
protected override void LoadViewState(object savedState)
{
//if we can identify the custom view state as defined in the override for SaveViewState
if (savedState is object[] && ((object[])savedState).Length == 2 && ((object[])savedState)[0] is string[])
{
object[] newViewState = (object[])savedState;
string[] txtValues = (string[])(newViewState[0]);
if (ViewState["Stu"] != null)
Students = (DataTable)ViewState["Stu"];
if (txtValues.Length > 0)
{
//re-load tables
CreateDynamicTable();
int i = 0;
foreach (TableRow row in tbl.Controls)
{
foreach (TableCell cell in row.Controls)
{
if (cell.Controls[0] is TextBox && i < txtValues.Length)
{
((TextBox)cell.Controls[0]).Text = txtValues[i++].ToString();
}
}
}
}
//load the ViewState normally
base.LoadViewState(newViewState[1]);
}
else
{
base.LoadViewState(savedState);
}
}
Now if you examine CreateDynamicTable() function, particularly the line:
int tblRows = Int32.Parse(NoTxt.Text);
you can see that the user can control the number of rows by entering a number in the TextBox NoTxt. When I run this code I get the following error:
An exception of type 'System.FormatException' occurred in mscorlib.dll but was not handled in user code
Additional information: Input string was not in a correct format.
and the error location is in the same line above.
The question is: How can I let the user control the number of rows in the table?
After few days of reading and research, the solution can be done by using Session variables. Store the value obtained in NoTxt.Text as follows for example:
Session["V"] = Int32.Parse(NoTxt.Text);
and retrieve it once you need it.
i am tired wondering the issue for this problem. have read so many blogs and forums for this but i am not able to find out the problem.
I am using "SQLServer" mode to store session.
Everything is working fine. But whenever i use search function in my website, it throws the below error:
"Unable to serialize the session state. In 'StateServer' and 'SQLServer' mode, ASP.NET will serialize the session state objects, and as a result non-serializable objects or MarshalByRef objects are not permitted. The same restriction applies if similar serialization is done by the custom session state store in 'Custom' mode."
I am assuming that this is because of the paging code i have used on that page. That code is as below:
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
string query = "select xxxxqueryxxxx";
SqlDataAdapter da = new SqlDataAdapter(query, con);
DataSet ds = new DataSet();
try
{
using (con)
{
con.Open();
da.Fill(ds);
}
}
catch
{
ds = null;
}
finally
{
if (ds != null)
{
CustomPaging page = new CustomPaging();
DataTable dt = ds.Tables[0];
page.PageSize = 10;
page.DataSource = dt;
page.CurrentPageIndex = 0;
no = 1;
Session["DT"] = dt;
Session["page"] = page;
bindData(page, dt);
//set these properties for multi columns in datalist
DataList2.RepeatColumns = 1;
DataList2.RepeatDirection = RepeatDirection.Horizontal;
}
}
}
}
void bindData(CustomPaging page, DataTable dt)
{
try
{
DataList2.DataSource = page.DoPaging;
DataList2.DataBind();
//DataList2.DataSource = SqlDataSource1;
//DataList2.DataBind();
lbtnPre.Enabled = !page.IsFirstPage; //Enable / Disable Navigation Button
// lbtnPre.CssClass = "disabledbtn";
lbtnNext.Enabled = !page.IsLastPage;
//lbtnNext.CssClass = "disabledbtn";
lblStatus.Text = NavigationIndicator(); //Build Navigation Indicator
//for creating page index
DataTable dt1 = new DataTable();
dt1.Columns.Add("PageIndex");
dt1.Columns.Add("PageText");
for (int i = 0; i < page.PageCount; i++)
{
DataRow dr = dt1.NewRow();
dr[0] = i;
dr[1] = i + 1;
dt1.Rows.Add(dr);
}
dlPaging.DataSource = dt1;
dlPaging.DataBind();
dlPaging.RepeatColumns = 10;
dlPaging.RepeatDirection = RepeatDirection.Horizontal;
}
catch (Exception)
{
}
finally
{
page = null;
}
}
string NavigationIndicator()
{
string str = string.Empty; //Page x Of Y
str = Convert.ToString(((CustomPaging)Session["page"]).CurrentPageIndex + 1) + " of " + ((CustomPaging)Session["PAGE"]).PageCount.ToString() + " Page(s) found";
return str;
}
protected void lbtnPre_Click(object sender, EventArgs e)
{
int pageIndex = ((CustomPaging)Session["page"]).CurrentPageIndex;
if (!((CustomPaging)Session["page"]).IsFirstPage)
//Decrements the pageIndex by 1 (Move to Previous page)
((CustomPaging)Session["page"]).CurrentPageIndex -= 1;
else
((CustomPaging)Session["page"]).CurrentPageIndex = pageIndex;
//Binds the DataList with new pageIndex
bindData(((CustomPaging)Session["page"]), ((DataTable)Session["DT"]));
}
protected void lbtnNext_Click(object sender, EventArgs e)
{
int pageIndex = ((CustomPaging)Session["page"]).CurrentPageIndex;
if (!((CustomPaging)Session["page"]).IsLastPage)
//Increments the pageIndex by 1 (Move to Next page)
((CustomPaging)Session["page"]).CurrentPageIndex += 1;
else
((CustomPaging)Session["page"]).CurrentPageIndex = pageIndex;
//Binds the DataList with new pageIndex
bindData(((CustomPaging)Session["page"]), ((DataTable)Session["DT"]));
}
protected void DataList2_SelectedIndexChanged(object sender, EventArgs e)
{
Response.Redirect("Default2.aspx?partnumber=" + DataList2.DataKeyField[DataList2.SelectedIndex].ToString());
}
protected void dlPaging_ItemCommand(object source, DataListCommandEventArgs e)
{
if (e.CommandName == "Select")
{
no = int.Parse(e.CommandArgument.ToString()) + 1;
((CustomPaging)Session["page"]).CurrentPageIndex = int.Parse(e.CommandArgument.ToString());
//Binds the DataList with new pageIndex
bindData(((CustomPaging)Session["page"]), ((DataTable)Session["DT"]));
}
}
protected void dlPaging_ItemDataBound(object sender, DataListItemEventArgs e)
{
LinkButton btn = (LinkButton)e.Item.FindControl("lnkbtnPaging");
if (btn.Text == no.ToString())
{
btn.ForeColor = System.Drawing.Color.Maroon;
btn.Font.Underline = false;
}
else
{
btn.ForeColor = System.Drawing.Color.DarkCyan;
btn.Font.Underline = false;
}
}
I just want to know what the problem is in the coding and "how to serialize the session"?
What shold i do to improve the coding?
Any help will be appreciated.
Thank You
I guess your custom paging control is not serializable. This must be the cause of the issue.
Anyway, storing a control in session is not a good idea. Just store the few serializable properties which enable to rebuild the control (PageSize and CurrentPageIndex), or pass them in query string for example.
You could also use ViewState if you can
About storing the DataTable in Session, this might be a really bad idea if you have a lot of data and many connected users.
On Page Load Event I am trying to do
protected void Page_Load(object sender, EventArgs e)
{
XmlReader reader = XmlReader.Create(FeedUrl);
SyndicationFeed feed = SyndicationFeed.Load(reader);
lstViewNewsFeeds.DataSource = feed.Items;
lstViewNewsFeeds.DataBind();
}
protected void lstViewNewsFeeds_ItemDataBound(object sender, ListViewItemEventArgs e)
{
try
{
// Instantiate listview control object.
ListViewDataItem lvDataItem = (ListViewDataItem)e.Item;
at this line given exception
**DataRowView drvItem = (DataRowView)lvDataItem.DataItem;**
//Make sure that data item is binding with listview.
if (lvDataItem.ItemType == ListViewItemType.DataItem)
{
SyndicationItem item = e.Item.DataItem as SyndicationItem;
LinkButton linkButtonTitle = (LinkButton)e.Item.FindControl("lbNewsTitle");
Panel panelNewsDescContent = (Panel)e.Item.FindControl("panelNewsDescription");
// Make sure that linkButtonTile is referenced.
if (linkButtonTitle != null)
{
// linkButtonTitle.Text = Convert.ToString(item.Title);
linkButtonTitle.Text = Convert.ToString(drvItem["Title"]);
}
// Make sure that panel object is referenced.
if (panelNewsDescContent != null)
{
Label lblBox = new Label();
// lblBox.Text = Convert.ToString(item.Summary);
panelNewsDescContent.Controls.Add(lblBox);
}
//Label l = e.Row.FindControl("Label1") as Label;
//l.Text = item.Title.Text;
//HyperLink hl = e.Row.FindControl("HyperLink1") as HyperLink;
//hl.Text = item.Title.Text;
//hl.NavigateUrl = item.Links[0].Uri.AbsoluteUri;
}
}
catch(Exception ee)
{
Response.Write(ee.Message);
}
Giving Error:
'System.Data.DataRowView'.Unable to cast object of type
'System.ServiceModel.Syndication.SyndicationItem' to type
'System.Data.DataRowView'.Unable to cast object of type
I am not able to understand how i remove this error. Please help me here.
SyndicationFeed.Items Property returns an IEnumerable<SyndicationItem>, so you should cast it to SyndicationItem instead.
SyndicationItem item = (SyndicationItem)lvDataItem.DataItem;
i have tried this works fine.
SyndicationItem item = e.Item.DataItem as SyndicationItem;
protected void lstViewNewsFeeds_ItemDataBound(object sender, ListViewItemEventArgs e)
{
try
{
// Instantiate listview control object.
ListViewDataItem lvDataItem = (ListViewDataItem)e.Item;
//DataRowView drvItem = (DataRowView)lvDataItem.DataItem;
//SyndicationItem item = (SyndicationItem)lvDataItem.DataItem;
//Make sure that data item is binding with listview.
if (lvDataItem.ItemType == ListViewItemType.DataItem)
{
SyndicationItem item = e.Item.DataItem as SyndicationItem;
LinkButton linkButtonTitle = (LinkButton)e.Item.FindControl("lbNewsTitle");
Panel panelNewsDescContent = (Panel)e.Item.FindControl("panelNewsDescription");
// Make sure that linkButtonTile is referenced.
if (linkButtonTitle != null)
{
// linkButtonTitle.Text = Convert.ToString(item.Title);
linkButtonTitle.Text = Convert.ToString(item.Title.Text);
}
// Make sure that panel object is referenced.
if (panelNewsDescContent != null)
{
Label lblBox = new Label();
lblBox.Text = Convert.ToString(item.Summary);
panelNewsDescContent.Controls.Add(lblBox);
}
//Label l = e.Row.FindControl("Label1") as Label;
//l.Text = item.Title.Text;
//HyperLink hl = e.Row.FindControl("HyperLink1") as HyperLink;
//hl.Text = item.Title.Text;
//hl.NavigateUrl = item.Links[0].Uri.AbsoluteUri;
}
}
catch(Exception ee)
{
Response.Write(ee.Message);
}
}
By The way thanks all of you for help.
Try this:
protected void lstViewNewsFeeds_ItemDataBound(object sender, ListViewItemEventArgs e)
{
try
{
//Make sure that data item is binding with listview.
if (lvDataItem.ItemType == ListViewItemType.DataItem)
{
SyndicationItem item = e.Item.DataItem as SyndicationItem;
LinkButton linkButtonTitle = (LinkButton)e.Item.FindControl("lbNewsTitle");
Panel panelNewsDescContent = (Panel)e.Item.FindControl("panelNewsDescription");
// Make sure that linkButtonTile is referenced.
if (linkButtonTitle != null)
{
linkButtonTitle.Text = Convert.ToString(item.Title);
}
// Make sure that panel object is referenced.
if (panelNewsDescContent != null)
{
Label lblBox = new Label();
lblBox.Text = Convert.ToString(item.Summary);
panelNewsDescContent.Controls.Add(lblBox);
}
Label l = e.Row.FindControl("Label1") as Label;
l.Text = item.Title.Text;
HyperLink hl = e.Row.FindControl("HyperLink1") as HyperLink;
hl.Text = item.Title.Text;
hl.NavigateUrl = item.Links[0].Uri.AbsoluteUri;
}
}
catch(Exception ee)
{
Response.Write(ee.Message);
}
}
I was trying to create a table dynamically and put textboxes in it. Here in the following code, i was trying to create a textbox with a distinct name for each k. But only the last value of k is getting displayed in the textbox. I was wondering how i could give a name to Textbox so all are shown.
for (int k = 0; k < tblCols; k++)
{
TableCell tc = new TableCell();
TextBox txtCompanyName = new TextBox();
txtCompanyName.Text = dsmissing.Tables[0].Rows[tblCols- 1]["NewCompanyName"].ToString();
tc.Controls.Add(txtCompanyName);
}
Replace this line
dsmissing.Tables[0].Rows[tblCols- 1]["NewCompanyName"].ToString();
With
dsmissing.Tables[0].Rows[k]["NewCompanyName"].ToString();
I assume you are talking about ID like below.
for (int k = 0; k < tblCols; k++)
{
TableCell tc = new TableCell();
TextBox txtCompanyName = new TextBox();
txtCompanyName.Text = dsmissing.Tables[0].Rows[k]["NewCompanyName"].ToString();
txtCompanyName.ID = Guid.NewGuid().ToString("N");
tc.Controls.Add(txtCompanyName);
}
I think you may have meant to do this:
for (int k = 0; k < tblCols; k++)
{
TableCell tc = new TableCell();
TextBox txtCompanyName = new TextBox();
//txtCompanyName.Text = dsmissing.Tables[0].Rows[tblCols-1 ["NewCompanyName"].ToString();
txtCompanyName.Text = dsmissing.Tables[0].Rows[k]["NewCompanyName"].ToString();
tc.Controls.Add(txtCompanyName);
}
Surely this will work and it is easy to understand
protected void Page_Load(object sender, EventArgs e)
{
button1();
}
protected void Page_Init(object sender, EventArgs e)
{
try
{
Label lbl = new Label();
lbl.ID = "lbl_label";
lbl.Text = "Enter the values";
form1.Controls.Add(lbl);
TextBox tb = new TextBox();
tb.ID = "tbx_textbox";
form1.Controls.Add(tb);
Button bt = new Button();
bt.ID = "bt_button";
bt.Text = "click";
form1.Controls.Add(bt);
}
catch (Exception ex) { }
}
public void button1()
{
Table table = new Table();
TableRow row = null;
TableCell cell = null;
TextBox tbx1 = this.Page.FindControl("tbx_textbox") as TextBox;
try
{
int a = int.Parse(tbx1.Text);
for (int i = 0; i < a; i++)
{
row = new TableRow();
cell = new TableCell();
TextBox tx = new TextBox();
tx.ID = "box" + i.ToString();
cell.Controls.Add(tx);
row.Cells.Add(cell);
table.Rows.Add(row);
form1.Controls.Add(table);
}
}
catch (Exception ex) { }
finally
{
table = null;
}
}