Develop Reference

Add Event on specific control in the gridview

I have a scenario, where i need to attach an event (textchanged) to a textbox. It should only trigger, if the code is "code2". Please check the below code ; The value_TextChanged doesn't get triggered:
<asp:GridView runat="server" ID="gv1" AutoGenerateColumns="false"
onrowcreated="gv1_RowCreated1" >
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:Label runat="server" ID="code" Text='<%# Bind("[code]") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField>
<ItemTemplate>
<asp:TextBox runat="server" ID="val" Text='<%# Bind("[value]") %>'></asp:TextBox>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
DataBind();
}
}
void DataBind()
{
DataTable dt = new DataTable();
dt.TableName = "tb1";
dt.Columns.Add("code");
dt.Columns.Add("value");
dt.Rows.Add("code1", "Red");
dt.Rows.Add("code2", "Green");
dt.Rows.Add("code3", "Blue");
gv1.DataSource = dt;
gv1.DataBind();
}
protected void gv1_RowCreated1(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
string code = (String)DataBinder.Eval(e.Row.DataItem, "code");
TextBox value = (TextBox)e.Row.FindControl("val");
if (code == "code2")
{
value.AutoPostBack = true;
value.TextChanged += new EventHandler(value_TextChanged);
}
}
}
void value_TextChanged(object sender, EventArgs e)
{
throw new NotImplementedException();
}

To trigger TextChange you need to add AutoPostBack="true" in your Markup; For attaching an event with TextChange you need not to depend gv1_RowCreated that also you can specify in the markup.
<asp:TextBox AutoPostBack="true" OnTextChanged="value_TextChanged"
runat="server" ID="val" Text="" ></asp:TextBox>
Please note one more thing, the event will trigger when the textBox
loss its focus

How to get value of a gridview cell in this scenario

I have a link button inside a gridView as below :
<asp:TemplateField HeaderText="Analyze">
<ItemTemplate>
<asp:LinkButton ID="LinkButton1" Text="Analyze" runat="server" OnClick="LinkButton1_Click" />
</ItemTemplate>
</asp:TemplateField>
I have the LinkButton1_Click function as below :
protected void LinkButton1_Click(object sender, EventArgs e)
{
testtb.Text = name;
Console.WriteLine(name);
}
This variable "name" is the first column of the GridView.I am obtaining the value for "name" as below:
protected void UnanalysedGV_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
DataRowView d = (DataRowView)e.Row.DataItem;
name = d["resultId"].ToString();
}
}
I want that on click of the link button the value of first column in that row of gridview becomes the text for the textbox testtb.
Somehow,the value for name remains null.
EDIT
I found out that probably RowDataBound isn't the correct event for my requirements because I need the value for each row.
So I removed the RowDataBound function.
I guess I have to handle this inside LinkButton1_Click itself.
I added this line to the function :
name = UnanalysedGV.SelectedRow.Cells[1].Text;
Still doesn't work.
Does anyone have any idea ?

You can do it using two approaches as mentioned below.
Handle click event of linkbutton through event bubbling code -
<asp:GridView AutoGenerateColumns="false" runat="server" ID="grdCustomPagging" OnRowCommand="grdCustomPagging_RowCommand">
<Columns>
<asp:BoundField DataField="RowNumber" HeaderText="RowNumber" />
<asp:BoundField DataField="DealId" HeaderText="DealID" />
<asp:BoundField DataField="Dealtitle" HeaderText="DealTitle" />
<asp:TemplateField HeaderText="View">
<ItemTemplate>
<asp:LinkButton runat="server" ID="lnkView" CommandArgument='<%#Eval("DealId") %>'
CommandName="VIEW">View Deal</asp:LinkButton>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
protected void grdCustomPagging_RowCommand(object sender, GridViewCommandEventArgs e)
{
if (e.CommandName == "VIEW")
{
LinkButton lnkView = (LinkButton)e.CommandSource;
string dealId = lnkView.CommandArgument;
}
}
Handle click event of linkbutton directly click event code -
<asp:GridView AutoGenerateColumns="false" runat="server" ID="grdCustomPagging">
<Columns>
<asp:BoundField DataField="RowNumber" HeaderText="RowNumber" />
<asp:BoundField DataField="DealId" HeaderText="DealID" />
<asp:BoundField DataField="Dealtitle" HeaderText="DealTitle" />
<asp:TemplateField HeaderText="View">
<ItemTemplate>
<asp:LinkButton runat="server" ID="lnkView" OnClick="lnkView_Click">View Deal</asp:LinkButton>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
protected void lnkView_Click(object sender, EventArgs e)
{
GridViewRow grdrow = (GridViewRow)((LinkButton)sender).NamingContainer;
string rowNumber = grdrow.Cells[0].Text;
string dealId = grdrow.Cells[1].Text;
string dealTitle = grdrow.Cells[2].Text;
}
Hope this helps.

ASP.NET Gridview ButtonField onclick fires containing row's onclick event

I have a gridview row that when clicked has to do postback A and a buttonfield in that row that when clicked has to do postback B. The problem is that when i click on the buttonfield, both event1 and event2 gets fired. Below is the code.
protected void gdv_RowCommand(object sender, GridViewCommandEventArgs e)
{
string arg = Convert.ToString(((System.Web.UI.WebControls.CommandEventArgs)(e)).CommandArgument);
if (e.CommandName == "Command1")
{
doEvent1(arg);
}
else if (e.CommandName == "Command2")
{
doEvent2(arg);
}
}
protected void gdv_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
LinkButton b1 = (LinkButton)e.Row.Cells[0].Controls[0];
matchesButton.CommandArgument = arg1;
LinkButton rowLink = (LinkButton)e.Row.Cells[1].Controls[1];
rowLink.CommandArgument = arg2;
e.Row.Attributes["onclick"] = ClientScript.GetPostBackClientHyperlink(rowLink, "");
}
}
And this is the asp code for the gridview
<Columns>
<asp:ButtonField DataTextField="f1" HeaderText="H1" CommandName="Command1" />
<asp:TemplateField>
<ItemTemplate>
<asp:LinkButton ID="btn1" runat="server" Text="" CommandName="Command2" />
</ItemTemplate>
</asp:TemplateField>
</Columns>

try to use this
protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
{
if (e.CommandName == "Command2")
{
// Your Code here
}
}
to find control in grid view use this code
LinkButton lnkbtn= (LinkButton)e.Row.FindControl("btn1");

Try adding both the button with in same <asp:TemplateField> if you don't want separate headers
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:Button ID="button" runat="server" CommandName="Command1" />
<asp:LinkButton ID="btn1" runat="server" CommandName="Command2" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
if you want separate headers make two separate <asp:TemplateField> and then add buttons in them.

In a GridView, how to add multiple commands to one item template?

I stripped this example to make it simple. I have a gridview with a template field. The template field contains two buttons and a label (They must be in the same template field). I want the first button to set the label text to "Win", and the other button to set the label text to "fail". The onrowcommand doesnt seem to be triggered by buttons in a template field. How can I accomplish this?
My gridview code is below:
<asp:GridView ID="GridView1" runat="server" EnableModelValidation="True" AutoGenerateColumns="False"
OnRowCommand="Gridview1_RowCommand">
<Columns>
<asp:TemplateField ShowHeader="False">
<ItemTemplate>
<asp:Button ID="btnWin" runat="server" CommandName="Win" Text="Win" />
<asp:Button ID="btnFail" runat="server" CommandName="Fail" Text="Fail" />
<asp:Label ID="lblStatus" runat="server" Text='<%# Bind("text") %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
and my code behind:
protected void Page_Load(object sender, EventArgs e)
{
DataTable myTable = new DataTable();
myTable.Columns.Add("text", typeof(string));
myTable.Rows.Add("First Entry");
myTable.Rows.Add("Second Entry");
GridView1.DataSource = myTable;
GridView1.DataBind();
}
public void Gridview1_RowCommand(Object sender, GridViewCommandEventArgs e)
{
//set lblStatus.text to "Win", or "Fail"
}
Thanks in advance!

Here you go...
public void Gridview1_RowCommand(Object sender, GridViewCommandEventArgs e)
{
lblStatus.Text = e.CommandName;
}
I see that there is more to this question than is answered here, bear with me. One way would be to delegate the OnCommand event of each button to its designated event handler, as follows:
<div>
<asp:GridView ID="MyGridView" runat="server" EnableModelValidation="true" AutoGenerateColumns="False">
<Columns>
<asp:TemplateField ShowHeader="False">
<ItemTemplate>
<asp:Button ID="MyWinButton" runat="server" OnCommand="MyWinButton_OnCommand" CommandName="Win" Text="Win" />
<asp:Label ID="MyStatusLabel" runat="server" Text='<%# Bind("text") %>'/>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
</div>
public void MyWinButton_OnCommand(Object sender, CommandEventArgs e)
{
var label = ((Button)sender).Parent.FindControl("MyStatusLabel") as Label;
label.Text = e.CommandName;
}
Also, as Alison suggests, you won't see the desired output of this unless you use !IsPostBack in Page_Load. Furthermore, on doing so this does in fact enable you to use the one row command event handler as initially suggested, albeit with a slight change in the label retrieval:
public void MyGridView_OnRowCommand(Object sender, GridViewCommandEventArgs e)
{
var label = ((Button)e.CommandSource).Parent.FindControl("MyStatusLabel") as Label;
label.Text = e.CommandName;
}

Are you using a MasterPage with ViewState turned off? Buttons in a template field with ViewState set to false will not fire.
Also, you should change your Page_Load to NOT rebind on postback"
protected void Page_Load(object sender, EventArgs e)
{
if (!page.IsPostBack) {
DataTable myTable = new DataTable();
myTable.Columns.Add("text", typeof(string));
myTable.Rows.Add("First Entry");
myTable.Rows.Add("Second Entry");
GridView1.DataSource = myTable;
GridView1.DataBind();
}
}
The rebinding may be interfering.

Find out a CHECKBOX in a DATAGRID in ASP.NET

I have a GRIDVIEW and with several CHECKBOXS.
When i selected a CHECKBOX I need run some code.
To detect it, I use an EVENT HANDLER for the CHECKBOX included in a GRIDVIEW.
I cannot access the CHECKBOX with my wrong code.
Do you have any idea what I am doing wrong? Thanks for your help. Bye
ASPX
<asp:Label ID="uxMessageDisplayer" runat="server" Visible="False" EnableViewState="False"></asp:Label>
<asp:GridView ID="uxUserListDisplayer" runat="server" AutoGenerateColumns="False"
OnRowDataBound="uxUserListDisplayer_RowDataBound">
<Columns>
<asp:TemplateField HeaderText="Active">
<ItemTemplate>
<asp:CheckBox ID="uxActiveCheckBoxSelector" runat="server" AutoPostBack="true" OnCheckedChanged="uxRoleCheckBoxSelector_CheckChanged" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField HeaderText="Users">
<ItemTemplate>
<asp:Label runat="server" ID="uxUserNameLabelDisplayer" Text='<%# Container.DataItem %>'></asp:Label>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField ShowHeader="False">
<ItemTemplate>
<asp:LinkButton ID="uxLinkEditButton" runat="server" CausesValidation="False" CommandName="Edit"
Text="Edit"></asp:LinkButton>
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField ShowHeader="False">
<ItemTemplate>
<asp:LinkButton ID="uxLinkDeleteButton" runat="server" CausesValidation="False" CommandName="Delete"
Text="Delete"></asp:LinkButton>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
CODE BEHIND
protected void uxRoleCheckBoxSelector_CheckChanged(object sender, EventArgs e)
{
// Reference the CheckBox that raised this event
//CheckBox uxActiveCheckBoxSelector = sender as CheckBox;
CheckBox activeCheckBox = (CheckBox)FindControl("uxActiveCheckBoxSelector");
if (activeCheckBox.Checked == true)
{
uxMessageDisplayer.Text = "T - Aproved User";
uxMessageDisplayer.Enabled = false;
}
else
{
uxMessageDisplayer.Text = "F - NOT Aproved User";
uxMessageDisplayer.Enabled = false;
}
}

If I am not mistaken by your question, you are trying to set the text of the label on the same row with the checkbox based on its checked status.
Below is the code snippet I tried on my pc, hope it helps.
.aspx:
<asp:GridView ID="GridView1" runat="server">
<Columns>
<asp:TemplateField>
<ItemTemplate>
<asp:CheckBox ID="CheckBox1" runat="server" OnCheckedChanged="CheckBox1_CheckChanged" AutoPostBack="true" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField>
<ItemTemplate>
<asp:Label ID="Label1" runat="server" Text=""></asp:Label>
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
.cs:
protected void Page_Load(object sender, EventArgs e)
{
if (Page.IsPostBack)
return;
//create dummy data
List<string> rows = new List<string>();
Enumerable.Range(1, 5).ToList().ForEach(x => rows.Add(x.ToString()));
//bind dummy data to gridview
GridView1.DataSource = rows;
GridView1.DataBind();
}
protected void CheckBox1_CheckChanged(object sender, EventArgs e)
{
//cast sender to checkbox
CheckBox CheckBox1 = (CheckBox)sender;
//retrieve the row where checkbox is contained
GridViewRow row = (GridViewRow)CheckBox1.NamingContainer;
//find the label in the same row
Label Label1 = (Label)row.FindControl("Label1");
//logics
if (CheckBox1 != null) //make sure checkbox1 is found
{
if (CheckBox1.Checked)
{
if (Label1 != null) //make sure label1 is found
{
Label1.Text = "Checked";
}
}
else
{
if (Label1 != null)
{
Label1.Text = "Unchecked";
}
}
}
}

I'm assuming the event handler is actually registered to the checkbox.
CheckBox activeCheckBox = (CheckBox)sender;
what is "uxActiveCheckBoxSelector" and why are you ignoring sender?

Code corrected as suggest!
Usefull resource for beginners
protected void uxRoleCheckBoxSelector_CheckChanged(object sender, EventArgs e)
{
// Cast sender to CheckBox
CheckBox activeCheckBox = (CheckBox)sender;
// Retrieve the row where CheckBox is contained (NamingContainer used to retrive parent control
GridViewRow row = (GridViewRow)activeCheckBox.NamingContainer;
if (activeCheckBox.Checked == true)
{
uxMessageDisplayer.Text = "T - Aproved User";
}
else
{
uxMessageDisplayer.Text = "F - NOT Aproved User";
}
}