How to disable Edit?

NOTE: not familiar with VB.. but you can use any of the online converter's to convert the example code in VB. or at least this will give you some idea.

You can use Gridview's onRowDataBound event for this purpose.

Get the Editbutton from specific row in this method as each row is bounded after traversing this event. and just disable this.

I hope this will give you some idea.

protected void YourGridview_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
    LinkButton lb = (LinkButton)(e.Row.Cells[0].Controls[0]); // if edit button is at index 0 i.e cell zero. or change it as per your req.

     string value = e.Row.Cells[2].Text; // if U wana disable it on some cell's specific value.
    if(value == "What you want")
        {
            lb.Visible = false;
        }

    }

}

Hope this will help. :)