Ive no problems using Javascript to read the rows of a telerik radgrid component im using however I can seem to find anyway to access the row data server side when a postback occurs. Ive spent ages looking for solution but no luck.
Any pointers would be greatly appreciated.
Tony
You might want to look at the DataKeyValues property of the OwnerTableView object, which will let you access a collection of values that represent the fields in a given row. I use it during the EditCommand event handler, since a user of my site is directed to an edit page if they click on the link to edit a row in the grid, and I need to pass along certain info about the given row in the query string.
If this turns out to be what you need, you'll also need to define which fields should be made available through this property. To do that, look at the MasterTableView.DataKeyNames property in the property sheet for the grid. You basically specify a comma-delimited list of field names.
The server-side is the easy part:
GridItemCollection gridRows = TestGrid.Items;
foreach (GridDataItem data in gridRows)
{
ItemClass obj = (ItemClass)data.DataItem;
}
It's the client side part that I don't know! :[
private Int32 GetID()
{
foreach (Telerik.Web.UI.GridDataItem dataItem in radGrid.MasterTableView.Items)
{
if (dataItem.Selected == true)
{
Int32 ID = (Int32)dataItem.GetDataKeyValue("ID");
return ID;
}
}
throw new ArgumentNullException("Id Not found");
}
This is the one that works for me and uses the RadGrid.SelectedItems collection.
protected void LinkButton1_Click(object sender, EventArgs e)
{
List<Guid> OrderIdList = new List<Guid>();
foreach (GridDataItem OrderItem in this.RadGrid1.SelectedItems)
{
OrderIdList.Add(new Guid(OrderItem.GetDataKeyValue("OrderId").ToString()));
}
}
If you correctly created your controls in markup or page init for dynamic controls, then the RadGrid will properly restore state.
You can access the initial values that were loaded from the data source like this example below, provided you told the table view in question to keep the columns around in the data keys.
protected T GetInitialGridData<T>(GridDataItem item, string uniqueColumnName) {
item.ThrowIfNull("item");
uniqueColumnName.ThrowIfNullOrEmpty("uniqueColumnName");
return (T)item.OwnerTableView.DataKeyValues(gridItem.ItemIndex)(columnName);
}
If you are using a dynamic custom template column, and need to get to any values that may now be in their states, you can use:
protected string GetCustomTextBoxValue(GridDataItem item, string controlID) {
item.ThrowIfNull("item");
controlID.ThrowIfNullOrTrimmedEmpty("controlID");
return ((TextBox)item.FindControl(controlID)).Text;
}
private Int32 GetID()
{
foreach (Telerik.Web.UI.GridDataItem dataItem in radGrid.MasterTableView.Items)
{
if (dataItem.Selected == true)
{
// Int32 ID = (Int32)dataItem.GetDataKeyValue("ID");
Int32 ID =Convert.ToInt32(dataItem.GetDataKeyValue("ID"));
return ID;
}
}
}
//this will work
Related
Is there a simple property or method to check whether a row changed or column value has been changed in my grid view. I also want to get the index of modified/changed row
You can add it to the gridview like this
<asp:GridView Name="gridview1" OnRowUpdating="GridViewUpdateEventHandler" />
If I remember correctly there is an abundance of tutorials for gridviews and how to manipulate data.
No, there is no simple property for that. But...
Here is a method for that on MSDN
You'll have to modify it for your data and your control names to verify, but it's all there, straight from the keyboard of Microsoft.
protected bool IsRowModified(GridViewRow r)
{
int currentID;
string currentLastName;
string currentFirstName;
currentID = Convert.ToInt32(GridView1.DataKeys[r.RowIndex].Value);
currentLastName = ((TextBox)r.FindControl("LastNameTextBox")).Text;
currentFirstName = ((TextBox)r.FindControl("FirstNameTextBox")).Text;
System.Data.DataRow row =
originalDataTable.Select(String.Format("EmployeeID = {0}", currentID))[0];
if (!currentLastName.Equals(row["LastName"].ToString())) { return true; }
if (!currentFirstName.Equals(row["FirstName"].ToString())) { return true; }
return false;
}
I am using a gridview in my asp.net project to view and modify some records from the database. The database has two columns: start_date and end_date. When a new record is created these columns contains null, but they can be modified later using the gridview update command.
In gridview I have two template fields (having names start_date and end_date) in which I have placed two calendar controls. Upon clicking an update link of gridview it always returns an error because of the null value binding to the calendar. I have used this helper function to solve it:
protected DateTime ReplaceNull(Object param)
{
if (param.Equals(DBNull.Value))
{
return DateTime.Now;
}
else
{
return Convert.ToDateTime(param);
}
}
and used these two custom expressions in calendar control's SelectedDate:
ReplaceNull(Eval("start_date"))
ReplaceNull(Eval("end_date"))
The problem is that two-way data binding the calendars upon selecting a date does not update the database table. Are there any workarounds? Or alternatively, a better solution would be appreciated.
I don't know why you let them null when insert a new record , but many ways you can solve this problem i think .
one of them : in the RowDataBound event of the Gridview
protected void gv_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
if (e.Row.Cells[1] == null) //the index of the start_date
{
e.Row.Cells[1].Text = DateTime.Now.ToString(); // in your case you will make the selected date of the calender(through casting to calender) with the value you need.
}
}
}
Or: you can catch the exception , you meet in your Update button through
try and catch block.
Here is what I am trying to do. I have a TreeView server side control (asp.net 2.0) and I need the user to be able to add nodes to it, then after all the nodes desired are added, the data should be saved to the database.
Here are some things I would like to pay attention to:
1) I don't want to save the tree data each time the new node is added, but rather keep the data in session until the user decides to save the entire tree. The question here is: can I bind the tree to ArrayList object and keep that object in session (rather than keeping the whole tree in session)? Then each time the node is added I will have to rebind the tree to the ArrayList rather than database.
2) I wish to minimize ViewState, any tips? What works best: compressing viewstate or keeping it all on the server at all times?
Thanks!
Use TreeNodeCollection as your internal array to hold in either ViewState or Session. Here's a rough mock-up of an approach you can use; far from perfect, but should set you on the right track.
TreeView tv = new TreeView();
// Button click event for 'Add Node' button
protected void AddNode(object sender, EventArgs e)
{
if (SaveNodeToDb(txtNewNode.Text, txtNavUrl.Text))
{
// Store user input details for new node in Session
Nodes.Add(new TreeNode() { Text = txtNewNode.Text, NavigateUrl = txtNavUrl.Text });
// Clear and re-add
tv.Nodes.Clear();
foreach (TreeNode n in Nodes)
tv.Nodes.Add(n);
}
}
public bool SaveNodeToDb(string name, string url)
{
// DB save action here.
}
public TreeNodeCollection Nodes
{
get
{
if (Session["UserNodes"] ! = null)
return (TreeNodeCollection) Session["UserNodes"];
else
return new TreeNodeCollection();
}
set
{
Session["UserNodes"] = value;
}
}
I want to bind a List to a GridView on a web page, but override the way the property names display via annotation. I thought System.ComponentModel would work, but this doesn't seem to work. Is this only meant for Windows Forms?:
using System.ComponentModel;
namespace MyWebApp
{
public class MyCustomClass
{
[DisplayName("My Column")]
public string MyFirstProperty
{
get { return "value"; }
}
public MyCustomClass() {}
}
Then on the page:
protected void Page_Load(object sender, EventArgs e)
{
IList<MyCustomClass> myCustomClasses = new List<MyCustomClass>
{
new MyCustomClass(),
new MyCustomClass()
};
TestGrid.DataSource = myCustomClasses;
TestGrid.DataBind();
}
This renders with "MyFirstProperty" as the column header rather than "My Column." Isn't this supposed to work?
When using .net 4 or later you can use gridview1.enabledynamicdata(typeof(mytype)). I haven't looked at all the types you can use there but I know the [displayname("somename")] works well but the [browsable(false)] doesn't omit the column from the grid. It looks like a knit one slip one from MS. at least you can easily rename column names and to omit a column I just declare a variable instead of using a property. It has the same effect...
Just by the way, using the designer to create columns is the easy way out but to just show a different column name takes way to much time especially with classes with many fields.
What SirDemon said...
The answer appears to be no, you can't. At least not out of the box.
The System.Web.UI.WebControls.GridView uses reflected property's name:
protected virtual AutoGeneratedField CreateAutoGeneratedColumn(AutoGeneratedFieldProperties fieldProperties)
{
AutoGeneratedField field = new AutoGeneratedField(fieldProperties.DataField);
string name = fieldProperties.Name; //the name comes from a PropertyDescriptor
((IStateManager) field).TrackViewState();
field.HeaderText = name; //<- here's reflected property name
field.SortExpression = name;
field.ReadOnly = fieldProperties.IsReadOnly;
field.DataType = fieldProperties.Type;
return field;
}
While System.Windows.Forms.DataGridView uses DisplayName if available:
public DataGridViewColumn[] GetCollectionOfBoundDataGridViewColumns()
{
...
ArrayList list = new ArrayList();
//props is a collection of PropertyDescriptors
for (int i = 0; i < this.props.Count; i++)
{
if (...)
{
DataGridViewColumn dataGridViewColumnFromType = GetDataGridViewColumnFromType(this.props[i].PropertyType);
...
dataGridViewColumnFromType.Name = this.props[i].Name;
dataGridViewColumnFromType.HeaderText = !string.IsNullOrEmpty(this.props[i].DisplayName) ? this.props[i].DisplayName : this.props[i].Name;
}
}
DataGridViewColumn[] array = new DataGridViewColumn[list.Count];
list.CopyTo(array);
return array;
}
Unfortunately, while you can override the CreateAutoGeneratedColumn, neither the missing DisplayName nor underlying property descriptor gets passed, and you can't override CreateAutoGeneratedColumns (although you could CreateColumns).
This means you'd have to iterate over reflected properties yourself and in some other place.
If all you care about is the header text in GridView, just use the HeaderText property of each field you bind. If you're autogenerating the columns, you just set the HeaderText after you've bound the GridView.
If you want a GridView that takes into account some attribute you placed on the properties of your bound class, I believe you'll need to create your own GridView.
I may be wrong, but I've not seen any ASP.NET Grid from control vendors (at least Telerik , Janus Systems and Infragistics) do that. If you do it, maybe sell the idea to them.
Are you using .net4, what you need to do is to set enabledynamicdata on the grid view to true.
You can do it now on asp.net mvc2. It works just like that
I'd like to add rows to an UltraWebGrid directly on the grid, which is connected to an ObjectDataSource. According to the documentation, I'm supposed to use the InsertDBRow method (there are also UpdateDBRow and DeleteDBRow) to handle database persistence.
Does anyone has any example on what's the supposed usage of these methods? (I already tried the help and Infragistics forums, with no success)
I'm planning on using this grid on a web page for fast data entry. If anyone has any tips toward this end, I'd most appreciate it.
I'm using Infragistics 2008 v1, ASP.Net.
You can use a generic function to handle the CRUD of the grid or call one of the DBRow(InsertDBRow, UpdateDBRow & DeleteDBRow) function directly each time. Example you can find below:
protected void UltraWebGrid_UpdateRow(object sender, Infragistics.WebUI.UltraWebGrid.RowEventArgs e)
{
CRUDHelper(e, UltraWebGrid);
}
private void CRUDHelper(Infragistics.WebUI.UltraWebGrid.RowEventArgs e, UltraWebGrid pUltraWebGrid)
{
switch (e.Row.DataChanged)
{
case Infragistics.WebUI.UltraWebGrid.DataChanged.Added:
pUltraWebGrid.InsertDBRow(e.Row);
break;
case Infragistics.WebUI.UltraWebGrid.DataChanged.Modified:
pUltraWebGrid.UpdateDBRow(e.Row);
break;
case Infragistics.WebUI.UltraWebGrid.DataChanged.Deleted:
pUltraWebGrid.DeleteDBRow(e.Row);
break;
}
}
You should be able to create a new instance of the UltraGridRow class and pass it to the UltraWebGrid's InsertDBRow method.
Here's an example of inserting a row using InsertDBRow.
// Create new UltraGridRow (using the object[] constructor)
var newRow = new UltraGridRow( new[] { "My First Value" , "My Second Value" } );
UltraWebGrid1.InsertDBRow( newRow );