Gridview Row_Command is not Firing

 Partial Class _Default
    Inherits System.Web.UI.Page
    Dim objCls As New CommClass
    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

    End Sub
    Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim str As String = "Select SrNo,Name From Mst_Login order by Name"
        Dim ds As New DataSet()
        ds = objCls.GetDs(str)
        GridView1.DataSource = ds.Tables(0)
        GridView1.DataBind()
    End Sub
    Protected Sub GridView1_RowCommand(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewCommandEventArgs) Handles GridView1.RowCommand
        txt1.Text = e.CommandArgument
    End Sub
    Protected Sub GridView1_RowDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewRowEventArgs) Handles GridView1.RowDataBound
        Try

            If e.Row.RowType = DataControlRowType.DataRow Then
                Dim LnkTest As New LinkButton()
                LnkTest.ID = "myID"
                LnkTest.CommandArgument = e.Row.Cells(0).Text
                LnkTest.Text = e.Row.Cells(0).Text
                AddHandler LnkTest.Click, AddressOf GridView1_RowCommand
                e.Row.Cells(0).Controls.Add(LnkTest)
            End If
        Catch ex As Exception

        End Try
    End Sub
End Class