access values of listview on code behind - asp.net

Question

I am creating a listview and binding data from database.
<asp:ListView runat="server" ID="lstService" DataTextField="Name"
DataValueField="Id" AutoPostBack="True">
<LayoutTemplate>
<table runat="server" id="table1">
<tr runat="server" id="itemPlaceholder"></tr>
</table>
</LayoutTemplate>
<ItemTemplate>
<tr runat="server">
<td runat="server">
<asp:Label ID="NameLabel" runat="server"
Text='<%#Eval("Name") %>' Width="500px" Height="30px" />
<asp:Button CssClass="btn btn-default" ID="srvButton" runat="server"
Text="Add" OnClick="srvButton_Click" />
<div class="voffset3"></div>
</td>
</tr>
</ItemTemplate>
</asp:ListView>
On code behind I am binding data on this field. I am fetching ID, Name column.
Now it is showing label and button with text "Add" on the button. But when I click on Add , I want to pass the value of "Id" associated with that list view item, how can I do that ?
protected void srvButton_Click(object sender, EventArgs e)
{
}

Answer 1

First add the CommandArgument to your Button with the value of the item Id:
<asp:Button CssClass="btn btn-default" ID="srvButton" runat="server" Text="Add" OnClick="srvButton_Click" CommandArgument='<%#Eval("Id")' />
Now you can access it in the srvButton_Click handler:
protected void srvButton_Click(object sender, EventArgs e)
{
Button myButton = (Button)sender;
int i = Convert.ToInt32(myButton.CommandArgument.ToString());
//----
}

Answer 2

You can change the OnClick to an OnCommand and send a CommandArgument along with it.
<asp:Button CssClass="btn btn-default" ID="srvButton" runat="server"
Text="Add" OnCommand="srvButton_Command" CommandArgument=<%# Eval("ID") %> />
And then in code behind
protected void srvButton_Command(object sender, CommandEventArgs e)
{
int id = Convert.ToInt32(e.CommandArgument);
}
Or you can use OnItemCommand event of the ListView along with the DataKeyNames property and use a button without an event bound to it.
<asp:ListView runat="server" ID="lstService" DataKeyNames="id"
OnItemCommand="lstService_ItemCommand">
<asp:Button CssClass="btn btn-default" ID="srvButton" runat="server" Text="Add" />
And then in code behind get the datakey from the ListView.
protected void lstService_ItemCommand(object sender, ListViewCommandEventArgs e)
{
int id = Convert.ToInt32(lstService.DataKeys[e.Item.DataItemIndex].Values[0]);
}