How can I tell which button in a repeater got pressed?

Question

I have the following markup in an .aspx file:

<asp:Repeater ID="ListOfAssignments" runat="server" OnItemDataBound="ListOfAssignments_ItemDataBound">
    <ItemTemplate>

        <asp:Label ID="AssignmentID" runat="server" Text="Label"></asp:Label>
        <br />
        <asp:Label ID="PathToFile" runat="server" Text="Label"></asp:Label>
        <br />
        <asp:Button ID="RemoveAssignment" runat="server" Text="Remove" OnClick="RemoveAssignment_Click"/>

    </ItemTemplate>
</asp:Repeater>

There are two labels and a button in a fairly standard repeater control. The repeater is bound to a database, and populates the labels with records from the database.

Here's my problem: I have a click event for each button in the repeater. The RemoveAssignment_Click method is called when the user clicks any of the buttons. In the click event, I want to know the text of the two labels associated with whatever button the user clicked.

What I mean is, in this method:

protected void RemoveAssignment_Click(object sender, EventArgs e)
{
    //code goes here
}

I want to be able to know the text of the labels that are adjacent to the button that was clicked. How do I do that?

Answer 1

What you are looking for is the Button.OnCommand Method:

This allows you to create multiple Button controls on a Web page and programmatically determine which Button control is clicked.

So inside ListOfAssignments_ItemDataBound you'd assign the CommandArgument to the button, where the CommandArgument is the ID of the article to be deleted:

protected void ListOfAssignments_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
    if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
    {
        Button delButton = e.Item.FindControl("RemoveAssignment") as Button;
        delButton.CommandArgument = //set to the value of AssignmentID
        //rest of your code
    }
}

And now your button should say to use your new OnCommand:

<asp:Button ID="RemoveAssignment" OnCommand="RemoveAssignment" runat="server" Text="Remove" />

And then you create the method:

protected void RemoveAssignment(object sender, CommandEventArgs e)
{
    int articleIDToDelete = 0;
    if (Int32.TryParse((string)e.CommandArgument, out articleIDToDelete))
    {
        //delete the article with an ID = articleIDToDelete
    }
}