Get DataKey values in GridView RowCommand

Question

I have a GridView with an associated DataKey, which is the item ID. How do I retrieve that value inside the RowCommand event?

This seems to work, but I don't like the cast to LinkButton (what if some other command is firing the event?), and I'm not too confident about the NamingContainer bit.

LinkButton lb = (LinkButton)e.CommandSource;
GridViewRow gvr = (GridViewRow)lb.NamingContainer;
int id = (int)grid.DataKeys[gvr.RowIndex].Value;

I'm aware that I could instead pass that ID as the CommandArgument, but I chose to use DataKey to give me more flexibility.

I'm also aware that it's possible to use a hidden field for the ID, but I consider that a hack that I don't want to use.

Answer 1

I usually pass the RowIndex via CommandArgument and use it to retrieve the DataKey value I want.

On the Button:

CommandArgument='<%# DataBinder.Eval(Container, "RowIndex") %>'

On the Server Event

int rowIndex = int.Parse(e.CommandArgument.ToString());
string val = (string)this.grid.DataKeys[rowIndex]["myKey"];

Answer 2

I managed to get the value of the DataKeys using this code:

In the GridView I added:

DataKeyNames="ID" OnRowCommand="myRowCommand"

Then in my row command function:

protected void myRowCommand(object sender, GridViewCommandEventArgs e) 
{
    LinkButton lnkBtn = (LinkButton)e.CommandSource;    // the button
    GridViewRow myRow = (GridViewRow)lnkBtn.Parent.Parent;  // the row
    GridView myGrid = (GridView)sender; // the gridview
    string ID = myGrid.DataKeys[myRow.RowIndex].Value.ToString(); // value of the datakey 

    switch (e.CommandName)
    {
      case "cmd1":
      // do something using the ID
      break;
      case "cmd2":
      // do something else using the ID
      break;
    }
 }

Answer 3

foreach (GridViewRow gvr in gvMyGridView.Rows)
{
    string PrimaryKey = gvMyGridView.DataKeys[gvr.RowIndex].Values[0].ToString();
}

You can use this code while doing an iteration with foreach or for any GridView event like OnRowDataBound.

Here you can input multiple values for DataKeyNames by separating with comma ,. For example, DataKeyNames="ProductID,ItemID,OrderID".

You can now access each of DataKeys by providing its index like below:

string ProductID = gvMyGridView.DataKeys[gvr.RowIndex].Values[0].ToString();
string ItemID = gvMyGridView.DataKeys[gvr.RowIndex].Values[1].ToString();
string OrderID = gvMyGridView.DataKeys[gvr.RowIndex].Values[2].ToString();

You can also use Key Name instead of its index to get the values from DataKeyNames collection like below:

string ProductID = gvMyGridView.DataKeys[gvr.RowIndex].Values["ProductID"].ToString();
string ItemID = gvMyGridView.DataKeys[gvr.RowIndex].Values["ItemID"].ToString();
string OrderID = gvMyGridView.DataKeys[gvr.RowIndex].Values["OrderID"].ToString();

Answer 4

you can just do this:

string id = GridName.DataKeys[Convert.ToInt32(e.CommandArgument)].Value.ToString();

Answer 5

On the Button:

CommandArgument='<%# Eval("myKey")%>'

On the Server Event

e.CommandArgument