asp.net - GridView dynamic footer row creation problem - asp.net

I am able to create BoundFields and Footer-rows dynamically like this in my GridView:
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
CreateGridView();
}
}
private void CreateGridView()
{
GridView1.Columns.Clear();
DataTable dataTable = Book.GetBooksDataSet().Tables[0];
CommandField cf = new CommandField();
cf.ShowEditButton = true;
GridView1.Columns.Add(cf);
int colCount = 1;
foreach (DataColumn c in dataTable.Columns)
{
BoundField boundField = new BoundField();
boundField.DataField = c.ColumnName;
boundField.HeaderText = c.ColumnName;
//boundField.FooterText = "---";
if (colCount == 3 || colCount == 5)
{
boundField.ReadOnly = true;
}
GridView1.Columns.Add(boundField);
colCount++;
}
GridView1.ShowFooter = true;
GridView1.DataSource = dataTable;
GridView1.DataBind();
GridViewRow footerRow = GridView1.FooterRow;
Button b = new Button();
b.Text = "Add New";
int i = 0;
footerRow.Cells[i].Controls.Add(b);
foreach (DataColumn c in dataTable.Columns)
{
++i;
TextBox tb = new TextBox();
footerRow.Cells[i].Controls.Add(tb);
}
}
....................................
....................................
....................................
}
But the problem is, when I click the "Add New" - button, it disappears instantly. And, also I am unable to add any event handler to it. Or intercept its actions like this:
protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
{
int index = Convert.ToInt32(e.CommandArgument);
if (e.CommandName == "Edit")
{
GridView1.EditIndex = index;
GridViewRow selectedRow = ((GridView)e.CommandSource).Rows[index];
//We can get cell data like this
string id = selectedRow.Cells[1].Text;
string isbn = selectedRow.Cells[2].Text;
//This is necessary to GridView to be showed up.
CreateGridView();
}
else if (e.CommandName == "Update")
{
LinkButton updateButton = (LinkButton)e.CommandSource;
DataControlFieldCell dcfc = (DataControlFieldCell)updateButton.Parent;
GridViewRow gvr = (GridViewRow)dcfc.Parent;
//The update...................
//Update grid-data to database
UpdateDataInTheDatabase(gvr.Cells[1].Controls);
//Grid goes back to normal
GridView1.EditIndex = -1;
//This is necessary to GridView to be showed up.
CreateGridView();
}
}
One more thing, I have seen some solutions that suggests to handle the GridView's rowBound event. But I need to do it from within Page_load event handler, or in, GridView1_RowCommand event handler.

Dynamically created controls mus be re-created on every postback. Your "Add New" button causes a postback so the dynamically created footer disappears. Is there a reason this grid has to be created dynamically? From the code you posted it appears that you could do this in markup instead. If not, you'll have to re-create the dynamic controls on every postback.
Edited to add:
I played with this a little bit and what's below works in that the grid doesn't disappear and events are handled, but it doesn't actually do anything. Hope this helps.
Markup:
<p><asp:Literal ID="Literal1" runat="server" /></p>
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false"
OnRowCommand="GridView1_RowCommand"
OnRowEditing="GridView1_RowEditing"/>
Code:
protected void Page_Load(object sender, EventArgs e)
{
BindGridView();
}
private DataTable GetBooksDataTable()
{
var dt = new DataTable();
dt.Columns.Add("ID", typeof(int));
dt.Columns.Add("Title", typeof(string));
dt.Columns.Add("Author", typeof(string));
for (int index = 0; index < 10; index++)
{
dt.Rows.Add(index, "Title" + index, "Author" + index);
}
return dt;
}
private void BindGridView()
{
var dt = GetBooksDataTable();
GridView1.Columns.Clear();
GridView1.ShowFooter = true;
var cf = new CommandField();
cf.HeaderText = "Action";
cf.ShowEditButton = true;
GridView1.Columns.Add(cf);
for (int index = 0; index < dt.Columns.Count; index++)
{
var boundField = new BoundField();
boundField.DataField = dt.Columns[index].ColumnName;
boundField.HeaderText = dt.Columns[index].ColumnName;
GridView1.Columns.Add(boundField);
}
GridView1.DataSource = dt;
GridView1.DataBind();
var footer = GridView1.FooterRow;
var b = new LinkButton();
b.Text = "Add New";
b.CommandName = "Add New";
footer.Cells[0].Controls.Add(b);
for (int index = 1; index < dt.Columns.Count + 1; index++)
{
var tb = new TextBox();
footer.Cells[index].Controls.Add(tb);
}
}
protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
{
Literal1.Text = e.CommandName;
}
protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
{
Literal1.Text = "Editing row index " + e.NewEditIndex.ToString();
}

Move your code from Page_Load to Page_Init. Things added in the Page_Load last only for the lifecycle of one postback.
You'd then be able to add eventhandlers, intercept events etc.

Related

Edit,delete,update operations in SPgridview in sharepoint 2010 using Webparts

I have a list in my SharePoint site with name "Empdetails" and having columns (EmpName string, Empaddress string).
I have to bind the list data to the SpGridview with edit, delete, update functionality.
I am able to bind the list data to gridview successfully, but I am unable to provide edit, delete, update functionality to the gridview.
Code:
private void binddata()
{
SPWeb mySite = SPContext.Current.Web;
SPList myList = mySite.Lists["Empdetails"];
SPListItemCollection items = myList.Items;
//Here we will make a datatable and we will put our list data to the data table
DataTable table=new DataTable();
table.Columns.Add("EmpName", typeof(string));
table.Columns.Add("Empaddress", typeof(string));
// Create rows for each splistitem
DataRow row;
foreach (SPListItem result in items)
{
row = table.Rows.Add();
row["EmpName"] = result["EmpName"].ToString();
row["Empaddress"] = result["Empaddress"].ToString();
}
//binding data to gridview
GridView1.DataSource = table.DefaultView;
GridView1.DataBind();
}
You will need to write all of the code for updates and deletes. It is not provided automatically.
Personally, I would recommend using the out of the box List View web part that points to a Datasheet view rather than trying to create my own.
But if you must write custom code, your code above might be able to be simplified from this:
DataTable table = new DataTable();
table.Columns.Add("EmpName", typeof(string));
table.Columns.Add("Empaddress", typeof(string));
DataRow row;
foreach (SPListItem result in items)
{
row = table.Rows.Add();
row["EmpName"] = result["EmpName"].ToString();
row["Empaddress"] = result["Empaddress"].ToString();
}
to this:
DataTable table = items.GetDataTable();
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
Bindata();
}
}
public void Bindata()
{
SPWeb web = SPContext.Current.Web;
SPList list = web.Lists["VisualWebpart"];
DataTable dt = new DataTable();
dt.Columns.Add("Title", typeof(string));
foreach (SPListItem item in list.Items)
{
DataRow dr = dt.NewRow();
dr["Title"] = item["Title"].ToString();
dt.Rows.Add(dr);
}
GridView1.DataSource = dt;
GridView1.DataBind();
}
protected void grd_Insert(object sender, GridViewCommandEventArgs e)
{
if (e.CommandName == "Insert")
{
SPWeb currentWeb = SPContext.Current.Web;
SPList lst = currentWeb.Lists["VisualWebpart"];
SPListItemCollection myColl = lst.Items;
TextBox txtTitle = (TextBox)GridView1.FooterRow.FindControl("txtTitle");
SPListItem item = myColl.Add();
item["Title"] = txtTitle.Text;
item.Update();
txtTitle.Text = "";
Bindata();
}
}
protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
{
GridView1.EditIndex = e.NewEditIndex;
Bindata();
}
protected void GridView1_Cancel(object sender, GridViewCancelEditEventArgs e)
{
GridView1.EditIndex = -1;
Bindata();
}
protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
{
GridViewRow row = (GridViewRow)GridView1.Rows[e.RowIndex];
int Title = row.DataItemIndex;
SPWeb currentWeb = SPContext.Current.Web;
SPList lst = currentWeb.Lists["VisualWebpart"];
SPListItemCollection myColl = lst.Items;
int itemcount = myColl.Count;
for (int i = 0; i <= itemcount-1; i++)
{
SPListItem item = myColl[i];
if (Title==i)
{
myColl.Delete(i);
}
}
Bindata();
}
protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
GridViewRow row = (GridViewRow)GridView1.Rows[e.RowIndex];
int Title = row.DataItemIndex;
SPWeb currentWeb = SPContext.Current.Web;
SPList lst = currentWeb.Lists["VisualWebpart"];
SPListItemCollection myColl = lst.Items;
int itemcount = myColl.Count;
TextBox txtTit = (TextBox)GridView1.Rows[e.RowIndex].FindControl("txtTit");
string d = txtTit.Text;
for (int i = 0; i <= itemcount - 1; i++)
{
SPListItem item = myColl[i];
if (Title == i)
{
item["Title"] = d;
item.Update();
}
}
GridView1.EditIndex = -1;
Bindata();
}
}

Prepopulate gridview empty datasource

I use an gridview empty datasource for bulk insert, how would I prepopulate for instance Column A with the value of a drop down box? So far I have below, but its not working
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
TextBox tb = (TextBox)e.Row.FindControl("YourTextBoxID");
if(tb != null)
{
tb.Text = DropDownList1.SelectedItem.Text;
}
}
}
I don't understand what you mean with empty DataSource. I assume that you actully mean a DataSource which is populated automatically with a default value.
You could use a DataTable:
var tbl = new DataTable();
tbl.Columns.Add("ColumnA");
var defText = DropDownList1.SelectedItem.Text;
for(int i = 0; i < 1000; i++)
{
tbl.Rows.Add(defText);
}
GridView1.DataSource = tbl;
GridView1.DataBind();

find a control by id from Dynamically added Template field in GridView

Hi i added template field dynamically to gridview by implementing ITemplate interface.
The template field contains some controls like label and textboxes. how do i get these controls in row databound event.
I am not able to get when i do gridviewrow.findcontrol("id") as i do normally when we add templatefield from aspx page.
The way i added template field is like this
public class CustomGridViewColumn : ITemplate
{
ListItemType _liType;
string _columnName;
public CustomGridViewColumn(ListItemType type, string column)
{
_liType = type;
_columnName = column;
}
void ITemplate.InstantiateIn(System.Web.UI.Control container)
{
switch (_liType)
{
case ListItemType.Header:
Label lblHeader = new Label();
lblHeader.Text = _columnName;
container.Controls.Add(lblHeader);
break;
case ListItemType.Item:
Label lblItem = new Label();
lblItem.DataBinding += new EventHandler(lbl_DataBinding);
lblItem.ID = "lbl" + _columnName;
lblItem.ClientIDMode = ClientIDMode.Predictable;
container.Controls.Add(lblItem);
DropDownList ddl = new DropDownList();
ddl.DataBinding += new EventHandler(ddl_DataBinding);
ddl.ID = "ddl" + _columnName;
ddl.Visible = false;
container.Controls.Add(ddl);
break;
}
}
}
Now i want access the label and dropdown which i have added using this code.
when i do gridviewrow.findcontrol("id") i am not getting them.
Can any one please help me.
I am geeting when i go through all the rows and try to find but
i have a check box in a row when i select it all labels should diappear and ddls dhould appear
for this i am using the follwoing code.
protected void chkEdit_CheckedChanged(object sender, EventArgs e)
{
CheckBox chkEditTest = (CheckBox)sender;
GridViewRow grow = (GridViewRow)chkEditTest.NamingContainer;
DropDownList ddl = (DropDownList)grow.FindControl("ddl");
Label lbl= (Label)grow.FindControl("lbl");
}
when i do this i am not able to get the controls.
it seems like controls are disapppearing on postback..
This is what I came up with and I can able to get the control reference in the code behind.
public class CustomGridViewColumn : ITemplate
{
ListItemType _liType; string _columnName;
public CustomGridViewColumn(ListItemType type, string column)
{
_liType = type;
_columnName = column;
}
void ITemplate.InstantiateIn(Control container)
{
switch (_liType)
{
case ListItemType.Header:
Label lblHeader = new Label();
lblHeader.Text = _columnName;
container.Controls.Add(lblHeader);
break;
case ListItemType.Item:
Label lblItem = new Label();
lblItem.DataBinding += new EventHandler(lblItem_DataBinding);
lblItem.ID = "lbl" + _columnName;
lblItem.ClientIDMode = ClientIDMode.Predictable;
container.Controls.Add(lblItem);
DropDownList ddl = new DropDownList();
ddl.DataBinding += new EventHandler(ddl_DataBinding);
ddl.ID = "ddl" + _columnName;
ddl.Visible = false;
ddl.DataSource = new string[] { "Hello", "World" };
container.Controls.Add(ddl);
break;
}
}
void ddl_DataBinding(object sender, EventArgs e)
{
}
void lblItem_DataBinding(object sender, EventArgs e)
{
}
}
protected void Page_Load(object sender, EventArgs e)
{
DataTable dt = new DataTable();
dt.Columns.Add("Name");
DataRow oItem = dt.NewRow();
oItem[0] = "Deepu";
dt.Rows.Add(oItem);
oItem = dt.NewRow();
oItem[0] = "MI";
dt.Rows.Add(oItem);
GridView gv = new GridView();
gv.ID = "myGridView";
gv.AutoGenerateColumns = false;
BoundField nameColumn = new BoundField();
nameColumn.DataField = "Name";
nameColumn.HeaderText = "Name";
gv.Columns.Add(nameColumn);
TemplateField TmpCol = new TemplateField();
TmpCol.HeaderText = "Template Column";
gv.Columns.Add(TmpCol);
TmpCol.ItemTemplate = new CustomGridViewColumn(ListItemType.Item, "TEST");
gv.DataSource = dt;
gv.DataBind();
Form.Controls.Add(gv);
}
protected void Button1_Click(object sender, EventArgs e)
{
GridView gv = Form.FindControl("myGridView") as GridView;
foreach (GridViewRow item in gv.Rows)
{
var ddl = item.FindControl("ddlTest") as DropDownList;
if (ddl != null)
{
ddl.Visible = true;
}
var lbl = item.FindControl("lbl") as Label;
if (lbl != null)
{
lbl.Text = "hello";
}
}
}
<form id="form1" runat="server">
<asp:Button ID="Button1" runat="server" onclick="Button1_Click" Text="Button" />
</form>
Thanks
Deepu
Can you try using row index of GRIDVIEW control
var rowIndex = int.Parse(e.CommandArgument)
GridView1.Rows[rowIndex].FindControl("id")
Also refer
http://forums.asp.net/t/998368.aspx/1
http://www.codeproject.com/Articles/12021/Accessing-the-different-controls-inside-a-GridView
http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.gridviewrow.aspx
Thanks
Deepu

Capture DropDownList Index Change event inside of grid View

I am trying to capture the SelectedIndexChanged event for a drop down list I have put inside of a gridview control. It posts back fine, but does not go into my SelectedIndexChanged event handler. Here is my code
DropDownList myddl;
protected void Page_Load(object sender, EventArgs e)
{
this.myGridview.RowDataBound += new GridViewRowEventHandler(myGridview_RowDataBound);
myddl = new DropDownList();
myddl.SelectedIndexChanged += new EventHandler(myddl_SelectedIndexChanged);
if (!Page.IsPostBack)
{
List<Team> teams = giveMeTeams();
this.myGridview.DataSource = teams;
this.myGridview.AutoGenerateColumns = false;
BoundField col1 = new BoundField();
col1.DataField = "Name";
this.myGridview.Columns.Add(col1);
BoundField col2 = new BoundField();
col2.DataField = "Sport";
this.myGridview.Columns.Add(col2);
BoundField col3 = new BoundField();
col3.DataField = "Status";
this.myGridview.Columns.Add(col3);
this.myGridview.DataBind();
}
}
void myGridview_RowDataBound(object sender, GridViewRowEventArgs e)
{
myddl = new DropDownList();
myddl.SelectedIndexChanged += new EventHandler(myddl_SelectedIndexChanged);
List<string> items = new List<string>();
items.Add("good");
items.Add("bad");
myddl.DataSource = items;
myddl.AutoPostBack = true;
myddl.DataBind();
e.Row.Cells[2].Controls.Add(myddl);
}
void myddl_SelectedIndexChanged(object sender, EventArgs e)
{
string temp = "In Here"; //neve hits this code
}
private List<Team> giveMeTeams()
{
Teams teams = new Teams();
teams.Add(new Team("RedWings", "Hockey", "good"));
teams.Add(new Team("Lions", "Football", "bad"));
teams.Add(new Team("Packers", "Football", "good"));
return teams;
}
Any help is greatly appreciated.
Thanks,
Edited based on Comments
I have tried as you suggested...and am still not capturing the post back. here is my new code
void myGridview_RowCreated(object sender, GridViewRowEventArgs e)
{
DropDownList myddl = new DropDownList();
myddl = new DropDownList();
myddl.SelectedIndexChanged += new EventHandler(myddl_SelectedIndexChanged);
myddl.ID = "MyID" + e.Row.RowIndex.ToString();
e.Row.Cells[2].Controls.Add(myddl);
}
void myGridview_RowDataBound(object sender, GridViewRowEventArgs e)
{
DropDownList myddl = e.Row.FindControl("MyID" + e.Row.RowIndex.ToString()) as DropDownList;
//myddl.SelectedIndexChanged += new EventHandler(myddl_SelectedIndexChanged);
List<string> items = new List<string>();
items.Add("good");
items.Add("bad");
myddl.DataSource = items;
myddl.DataMember = "Status";
myddl.AutoPostBack = true;
myddl.DataBind();
e.Row.Cells[2].Controls.Add(myddl);
}
it is still not going into my myddl_SelectedIndexChanged() eventhandler.
Create that Dropdownlist in RowCreated of the Grid and assign an ID to it. Get the refrence to these Dropdowns in RowDataBound via e.Row.FindControl("MyDropdownlistID") and bound them to the Datasource. Create distinct Dropdownlist instances instead of referencing always the same

GridView Create Fields Dynamically

I would like somebody to help me to solve the following issue.
I have a gridview, where the fields are created dynamically from codebehind.
I would like to create with the same way(dynamically) a templateField which, if it is possible, to hold in it two button controls, having also and commandName.
To be more clear:
Headers-->> First Name, LastName, Print(Daily/Invoices)
Results -->> FooFName, FooLName, Daily | Invoice
The bold one text is what I am looking for.
I am posting also the methods and the way I use them to create the fields.
CreateBoundField(BillingSummaryGV, "Book_Date", "Date", "{0:dd/MM/yyyy}");
CreateButtonField(BillingSummaryGV, "Print", "Print(Daily)", ButtonType.Link,"");
BillingSummaryGV.DataSource = billingSummaries;
BillingSummaryGV.DataBind();
protected void CreateBoundField(GridView gv, string dataField, string headerText, string arrFormatingString) {
var bf = new BoundField {
DataField = dataField,
DataFormatString = arrFormatingString,
HeaderText = headerText
};
gv.Columns.Add(bf);
}
private void CreateButtonField(GridView gv, string text, string headerText, ButtonType buttonType, string commandName) {
var bfPrint = new ButtonField() {
ButtonType = buttonType,
Text = text,
HeaderText = headerText,
Visible = true,
CommandName = commandName
};
gv.Columns.Add(bfPrint);
}
I would appreciate any reply
thanks
You have to create a template class that implements ITemplate. See this example from MSDN. The code below extends my answer to this question to add a template column that displays Title|Author.
Markup:
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false"
OnRowCommand="GridView1_RowCommand"
OnRowEditing="GridView1_RowEditing"/>
Code:
protected void Page_Load(object sender, EventArgs e)
{
BindGridView();
}
private DataTable GetBooksDataTable()
{
var dt = new DataTable();
dt.Columns.Add("ID", typeof(int));
dt.Columns.Add("Title", typeof(string));
dt.Columns.Add("Author", typeof(string));
for (int index = 0; index < 10; index++)
{
dt.Rows.Add(index, "Title" + index, "Author" + index);
}
return dt;
}
private void BindGridView()
{
var dt = GetBooksDataTable();
GridView1.Columns.Clear();
GridView1.ShowFooter = true;
var cf = new CommandField();
cf.HeaderText = "Action";
cf.ShowEditButton = true;
GridView1.Columns.Add(cf);
for (int index = 0; index < dt.Columns.Count; index++)
{
var boundField = new BoundField();
boundField.DataField = dt.Columns[index].ColumnName;
boundField.HeaderText = dt.Columns[index].ColumnName;
GridView1.Columns.Add(boundField);
}
CreateCustomTemplateField(GridView1, "Title|Author");
GridView1.DataSource = dt;
GridView1.DataBind();
var footer = GridView1.FooterRow;
var b = new LinkButton();
b.Text = "Add New";
b.CommandName = "Add New";
footer.Cells[0].Controls.Add(b);
for (int index = 1; index < dt.Columns.Count + 1; index++)
{
var tb = new TextBox();
footer.Cells[index].Controls.Add(tb);
}
}
private void CreateCustomTemplateField(GridView gv, string headerText)
{
var customField = new TemplateField();
customField.HeaderTemplate = new CustomTemplate(DataControlRowType.Header, headerText);
customField.ItemTemplate = new CustomTemplate(DataControlRowType.DataRow, headerText);
gv.Columns.Add(customField);
}
public class CustomTemplate : ITemplate
{
private DataControlRowType _rowType;
private string _headerText;
public CustomTemplate(DataControlRowType rowType, string headerText)
{
_rowType = rowType;
_headerText = headerText;
}
public void InstantiateIn(Control container)
{
switch (_rowType)
{
case DataControlRowType.Header:
var header = new Literal();
header.Text = _headerText;
container.Controls.Add(header);
break;
case DataControlRowType.DataRow:
var data = new Literal();
data.DataBinding += DataRowLiteral_DataBinding;
container.Controls.Add(data);
break;
}
}
private void DataRowLiteral_DataBinding(object sender, EventArgs e)
{
var data = (Literal)sender;
var row = (GridViewRow)data.NamingContainer;
data.Text = DataBinder.Eval(row.DataItem, "Title") + "|" + DataBinder.Eval(row.DataItem, "Author");
}
}
protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
{
Literal1.Text = e.CommandName;
}
protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
{
Literal1.Text = "Editing row index " + e.NewEditIndex.ToString();
}

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