Develop Reference

Problem with being able to access certain elements in GridView -> TemplateField -> EditItemTemplate

I have this problem with being able to access certain elements in
GridView -> TemplateField -> EditItemTemplate.
To be more clear, I have textbox and button
(in GridView -> TemplateField -> EditItemTemplate) and only one of them must be visible depending on operation. If I want to edit, button must be visible and if I want to add new user then textbox must be visible. I have added my aspx code for you to check and also C# code-behind. The method in C# code is the one which gets called immidiately when I press "Edit" button which lets to edit account details and permissions for one user. And I want that this method would decide whenever to show textbox or button (I have IsUserInsertMode property for that.)
I would be really grateful for someone who would help me out with this.
<asp:GridView CssClass="grid" ID="gridUsers" runat="server"
AutoGenerateColumns="False" DataKeyNames="id"
DataSourceID="dsrcUserList" GridLines="None"
OnRowCommand="gridUsers_RowCommand" OnDataBound="gridUsers_DataBound"
OnRowUpdating="gridUsers_Updating" OnRowUpdated="gridUsers_Updated" EnableModelValidation="True">
<Columns>
<asp:TemplateField HeaderText="Password" ItemStyle-HorizontalAlign="center" ItemStyle-Width="80px">
<ItemTemplate>
*******
</ItemTemplate>
<EditItemTemplate>
**NEED REFERENCES TO THESE TWO ITEMS IN ORDER TO SET THEIR VISIBILITY**
<asp:Button ID="btnEditPassword" Text="Change" runat="server" CausesValidation="false" OnClick="btnEditPassword_Click" Visible="false"/>
<asp:TextBox ID="txtPassword" runat="server" TextMode="Password" Text='<%# Bind("Password") %>' Width="74px" MaxLength="50" Visible="true" />
</EditItemTemplate>
</asp:TemplateField>
**LOTS OF CHECKBOXES LIKE THOSE**
<asp:CheckBoxField DataField="AccessTowsRelease" HeaderText="TowsRelease" ItemStyle-HorizontalAlign="Center">
<ItemStyle HorizontalAlign="Center"></ItemStyle>
</asp:CheckBoxField>
<asp:CheckBoxField DataField="AccessTowsView" HeaderText="TowsView" ItemStyle-HorizontalAlign="Center">
<ItemStyle HorizontalAlign="Center"></ItemStyle>
</asp:CheckBoxField>
<asp:CheckBoxField DataField="AccessSMS" HeaderText="SMS"
ItemStyle-HorizontalAlign="Center">
<ItemStyle HorizontalAlign="Center"></ItemStyle>
</asp:CheckBoxField>
**MY EDIT BUTTON**
<asp:CommandField ButtonType="Link"
ShowEditButton="true" EditText="Edit"
CancelText="Cancel" UpdateText="Save" />
</Columns>
</asp:GridView>
C# code-behind (I have added some of the stuff that I have tried)
// this is called when I press some button which lets me to edit one user data including password
// but when I want to change password, there should be button which would redirect to different
// window to do the password change procedure.
// And when I want to add new user there should be textbox for password, not the button.
protected void gridUsers_RowCommand(Object sender, GridViewCommandEventArgs e)
{
//Found the way to get the index of current row (represents one row of information which is visible for the client in browser)
int rowIndex = Convert.ToInt32(e.CommandArgument);
//if those would be working I wouldn't be here asking for help
btnEditPassword.Visible = true;
txtPassword.Visible = false;
//Can't cast 'System.Web.UI.WebControls.GridView' to type 'System.Web.UI.WebControls.GridViewRow'
Button btnEditPassword = (Button)((GridViewRow)sender).FindControl("btnEditPassword");
//every attempt to use FindControl gets me null
Button btnEditPassword = (Button)this.gridUsers.Rows[rowIndex].FindControl("btnEditPassword");
// my way to check if it works - if its null then I do can't anything (prints to browser console).
if (btnEditPassword != null) Response.Write("<script>console.log('not null')</script>");
else Response.Write("<script>console.log('null')</script>");
}

The RowCommand-event is raised too early for your case. It's raised before the row is going into edit mode, that's why you don't find the controls of your edit-item-template.
First change your markup to handle the RowDataBound-event:
<asp:GridView ... OnRowDataBound="gridUsers_OnRowDataBound" ...>
Then handle this in the OnRowDataBound-event like this:
protected void gridUsers_OnRowDataBound(object sender, GridViewRowEventArgs e) {
// check if row is in edit state
if ((e.Row.RowState == DataControlRowState.Edit) || (e.Row.RowState == (DataControlRowState.Alternate | DataControlRowState.Edit))) {
// look for the control in the row
Button btnEditPassword = (Button)e.Row.FindControl("btnEditPassword");
}
}

Asp.net checkbox renders span with AutoPostBack = true in it

This has got me at my wit's end. I have a GridView with a column with a checkbox in it. The checkbox is set to call CheckedChanged and AutoPostBack is true.
<asp:TemplateField>
<ItemTemplate>
<asp:CheckBox ID="cbNotifier" runat="server" OnCheckedChanged="cbNotifier_CheckedChanged" AutoPostBack="true" />
</ItemTemplate>
</asp:TemplateField>
I am using similar code in the first column of the GridView and it works perfectly. I am using the code above in a different column. It does not work. Instead of rendering the checkbox to do a postback, it renders a span around the checkbox like this:
<span AutoPostBack="true"><input id="cbNotifier" type="Checkbox"></span>
so, of course, the checkbox will not postback.
If I add another, identical checkbox to the same column, like this ...
<asp:TemplateField>
<ItemTemplate>
<asp:CheckBox ID="cbNotifier" runat="server" OnCheckedChanged="cbNotifier_CheckedChanged" AutoPostBack="true" />
<asp:CheckBox ID="cbNotifier1" runat="server" OnCheckedChanged="cbNotifier_CheckedChanged" AutoPostBack="true" />
</ItemTemplate>
</asp:TemplateField>
... the second checkbox postsback perfectly, the first one gets the span tag around it. What on earth is going on?

ASP.NET LinkButton not invoking 'OnCommand' event

I have a ListView nested inside the column of a GridView, which looks something like this:
<asp:panel id="myPanel" Runat="server" EnableViewState="False">
<asp:GridView id="myDescription" AutoGenerateColumns="False" Width="100%" runat="server"
OnRowCommand="my_RowCommand" OnRowDataBound="GetDataForListView" EnableViewState="False">
<Columns>
<asp:BoundField DataField="id" HeaderText="ID">
<HeaderStyle HorizontalAlign="Center"></HeaderStyle>
<ItemStyle HorizontalAlign="Center"></ItemStyle>
</asp:BoundField>
<asp:BoundField DataField="data1" HeaderText="Thing 1">
<HeaderStyle HorizontalAlign="Center"></HeaderStyle>
<ItemStyle HorizontalAlign="Center"></ItemStyle>
</asp:BoundField>
<asp:BoundField DataField="data2" HeaderText="Thing2">
<HeaderStyle HorizontalAlign="Center"></HeaderStyle>
<ItemStyle HorizontalAlign="Center"></ItemStyle>
</asp:BoundField>
<asp:BoundField DataField="data3" HeaderText="Thing3">
<HeaderStyle HorizontalAlign="Center"></HeaderStyle>
<ItemStyle HorizontalAlign="Center"></ItemStyle>
</asp:BoundField>
<asp:TemplateField SortExpression="id">
<ItemTemplate>
<asp:HyperLink id="hlView" runat="server" NavigateUrl="...">View</asp:HyperLink>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Column to contain my list of things">
<HeaderStyle HorizontalAlign="Center"></HeaderStyle>
<ItemStyle HorizontalAlign="Center"></ItemStyle>
<ItemTemplate>
<% /* This is my list view: */ %>
<asp:ListView ID="myListView" runat="server" OnItemCommand="DoSomething" EnableViewState="False">
<ItemTemplate>
<asp:LinkButton ID="lbAttachment" Runat="Server" Text='<%# Eval("FILE_NAME") %>'
CommandName='<%# Eval("ROW_NUM") %>' CausesValidation="False" >
</asp:LinkButton><br/>
</ItemTemplate>
</asp:ListView>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
</asp:panel>
The data is successfully binding, but the OnCommand event is not being fired on clicking the LinkButton (nor is any other event for the LinkButton, such as an OnClick event).
The rendered HTML for the link button shows that on clicking it, the page is performing a postback: javascript:__doPostBack('...','')
This means it is going back into my 'Page_Load' and refreshing the contents of the page - the grid view is binded here.
I can stop it from performing a postback by adding this attribute to the LinkButton:
OnClientClick="return false;"
But this only stops the postback from occurring, the OnCommand event still doesn't fire.
Any ideas?
The event signature in the code-behind is:
protected void DoSomething(object sender, CommandEventArgs e) { ... }
I have also tried using an OnItemCommand event on the ListView control with this event signature, but similarly the event is not invoked:
protected void DoSomething(object sender, ListViewCommandEventArgs e)
The OnRowdataBound event on the parent GridView is successfully invoked, it's only the nested ListView that fails to invoke its event.
The code I have shown is for the 2nd GridView on the page, there is another one too, and it is this one which gets binded on the Page_Load event. The Page Load event has a sequence of events as follows, where the 1st GridView (which we'll call GridView1) is bound:
Page_Load
Data for GridView is retrieved from database
Data is assigned to a 'DataView' object and assigned to the GridView1 DataSource property.
GridView1.DataBind() is invoked
Miscellaneous conditional logic which removes certain columns from GridView1
An OnClick attribute is added to each row.
So actually, the Page_Load binds the first GridView. The 2nd GridView is the one which contains the ListView which I am having a problem with. This 2nd GridView (the code of which is at the top of the post) is populated on the 'OnRowCommand' event of the 1st GridView, and has a sequence like this:
GetDataForListView
Get data from database
Assign the DataSet containing the data to the DataSource property of the 2nd GridView
Call the DataBind() method
Then, as you can see from the code I posted at the top, I have the OnRowDataBound event which fails to invoke its event in the code-behind.

Ciaran, I replicated the whole scenario and found out the below issue.
Issue: When any event related to either the GridView2 or ListView or the LinkButton is being fired it first hits the Page_load function. In the Page_load function you are not data binding GridView2 and the ListView so apparently they almost vanish and so the Event will not be fired.
Possible Fix:
You need to bind the GridView2 in the Page_load function in order fire those related events and the same goes with the ListView Too.
This fix is a very big one. I am not sure if you could try this.
a. If you are binding the GridView2 depending on the condition generated by the GridView1 click then store those parameters in some hidden field.
b. Have a function named LoadGridView2(parameters) where you bind the GridView2 and the ListView depending on the parameters passed and call this function in the Page_Load function each every time a PostBack is done and pass the stored parameters in the hidden field to the LoadGridView2(parameters)
c. By doing above you can bind the GridView2 according the GirdView1 Click condition and make the GridView2 and ListView available in the PostBack too. So now the event could be fired.
Let me know in case of any queries.

LinkButton has OnCommand, ListVIew has OnItemCommand. So the name isn't correct. OnCommand only fires if the LinkButton has a CommandName set. And also, the repeater may swallow the button's command argument. Certain controls do that because of the way events bubble up to the UI.
<asp:LinkButton ID="linkButton" Runat="Server" OnCommand="DoSomething"
CommandName="DoSomething"
CommandArgument='<%# Eval("ROW_NUM") %>' Text='<%# Eval("FILE_NAME") %>'>
</asp:LinkButton>
Or Try adding:
<asp:ListView .. OnItemCommand=".." />
And then do:
void DoSomething(Object Sender, ListViewCommandEventArgs e) {
// Do something
}
Your button would still need to set a command name like:
<asp:LinkButton .. CommandName="DoSomething" />

Change AutoGeneratedDelete LinkButton of Gridview to an Image Button

i have a gridview with AutoGenerateDeleteButton Property set true.
Of course this property auto generates a linkbutton at the leftmost of the gridview, my question is, how can i change it to an Image Button?? i wanted my gridview to look more presentable by making the control buttons an image.
Thanks! :)

You can do by using template in grid...
for more info
http://p2p.wrox.com/asp-net-2-0-professional/46216-image-button-template-field-gridview-control.html

You can create a TemplateField and use autogeneratecolumns="false".
Here's an example of a GridView:
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns ="false">
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:LinkButton ID="Link" runat="server" Text="click" OnClick="link_Click"/>
</ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="field1" HeaderText="My Column 1" />
<asp:BoundField DataField="field2" HeaderText="My Column 2" />
</Columns>
</asp:GridView>
Where field1 and field2 are headers from your DataTable
And to access the row within the event handler:
protected void link_Click(object sender, EventArgs e)
{
int rowindex = ((GridViewRow)((Control)sender).NamingContainer).RowIndex;
//do something with rowindex etc
}

Add new Template Column and in add image button and set CommandName='Delete' it'll raise the delete event automatically.
<asp:TemplateField>
<ItemTemplate>
<asp:ImageButton ID="imgDelete" ImageUrl="~/imgs/Delete.png"
CommandName="Delete" runat="server" />
</ItemTemplate>
</asp:TemplateField>

Try this
<Columns>
<asp:CommandField ButtonType="Image" DeleteImageUrl="~/Images/DeleteImage.png"
ShowDeleteButton="true"/>
</Columns>
And set AutoGenerateDeleteButton="false"
Or Refer this too

Adding dropdown list to columns in gridview

I have a grid and I want to set a dropdown list with Yes & No for some columns. I am not able to put that dropdown list like I mentioned below. Its because I use checkbox in the grid to edit the rows. So even if I put these I am not able to see the drop down when I click the checkbox to edit.
<asp:TemplateField HeaderText="Lead" ItemStyle-Width="100">
<ItemTemplate>
<asp:Label ID="lblLead" runat="server" Text='<%# Bind("Lead") %>'></asp:Label>
<asp:TextBox ID="txtLead" runat="server" Text='<%# Bind("Lead") %>' Visible="false"></asp:TextBox>
</ItemTemplate>
<ItemStyle Width="100px" />
<EditItemTemplate>
<asp:DropDownList id="ddlLead" runat="server">
<asp:ListItem Value="Yes"> Yes </asp:ListItem>
<asp:ListItem Value="No"> No </asp:ListItem>
</asp:DropDownList>
</EditItemTemplate>
</asp:TemplateField>

Try this
protected void grdVw_RowEditing(object sender, GridViewEditEventArgs e)
{
grdVw.EditIndex = e.NewEditIndex;
/* Insert specific editing logic here */
grdBind();//method to bind gridview
}

First you gotta make sure you are setting the mode to Edit. For this I use the default buttons, and you are using checkboxes, they should both work:
<asp:GridView ID="GridView1" runat="server" OnRowEditing="GridView1_RowEditing">
<Columns>
<asp:CommandField ShowEditButton="True" />
<%--Other columns here--%>
</Columns>
</asp:GridView>
Then, you need to handle the RowEditing event, by setting the EditIndex to the index of the row you want to edit, and re-bind the GridView:
protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
{
GridView1.EditIndex = e.NewEditIndex;
setDataSource(); //this sets the data source of the grid, and re-binds it.
}