[Solved] Remove Unwanted comma in ASP.Net Nested GridView Footer TextBox after PostBack

please help my footer textbox are getting this , comma sign

yet they are supposed to remain empty when no value has been inserted in them

Dim fName As String = DirectCast(StudentGrid.FooterRow.FindControl("Namesf"), TextBox).Text
Dim valueSEX As String = TryCast(StudentGrid.FooterRow.FindControl("ddlSexF"), DropDownList).SelectedItem.Value
Dim faddress As String = DirectCast(StudentGrid.FooterRow.FindControl("faddress"), TextBox).Text
Dim fphone As String = DirectCast(StudentGrid.FooterRow.FindControl("Fphone"), TextBox).Text
Dim fage As String = DirectCast(StudentGrid.FooterRow.FindControl("Fage"), TextBox).Text
Dim fdate As String = DirectCast(StudentGrid.FooterRow.FindControl("Fdates"), TextBox).Text

when i click

Protected Sub Button2_Click1(sender As Object, e As EventArgs)
    Dim fName As String = DirectCast(StudentGrid.FooterRow.FindControl("Namesf"), TextBox).Text
    Dim valueSEX As String = TryCast(StudentGrid.FooterRow.FindControl("ddlSexF"), DropDownList).SelectedItem.Value
    Dim faddress As String = DirectCast(StudentGrid.FooterRow.FindControl("faddress"), TextBox).Text
    Dim fphone As String = DirectCast(StudentGrid.FooterRow.FindControl("Fphone"), TextBox).Text
    Dim fage As String = DirectCast(StudentGrid.FooterRow.FindControl("Fage"), TextBox).Text
    Dim fdate As String = DirectCast(StudentGrid.FooterRow.FindControl("Fdates"), TextBox).Text
 
    If String.IsNullOrEmpty(fdate) Then
        fdate = Now
    End If
    If String.IsNullOrEmpty(valueSEX) Then
        ScriptManager.RegisterStartupScript(Me, [GetType](), "showalert", "alert('You Must Indicate whether Male Or Female');", True)
        TryCast(StudentGrid.FooterRow.FindControl("ddlSexF"), DropDownList).Focus()
        Exit Sub
    Else
        If String.IsNullOrEmpty(fName) Then
            ScriptManager.RegisterStartupScript(Me, [GetType](), "showalert", "alert('You Must Indicate Student Name');", True)
            TryCast(StudentGrid.FooterRow.FindControl("Namesf"), TextBox).Focus()
            Exit Sub
        Else
 
            Dim sqlConnection12 As New SqlConnection(conString)
            Dim objCommand22 As SqlCommand = New SqlCommand()
            Dim cmd2 As New SqlCommand
            cmd2.CommandText = "createaccounts"
            cmd2.CommandType = CommandType.StoredProcedure
            cmd2.Connection = sqlConnection12
            cmd2.Parameters.Add("@n", SqlDbType.NVarChar, 150).Value = fName
            cmd2.Parameters.Add("@s", SqlDbType.NVarChar, 12).Value = valueSEX
            cmd2.Parameters.Add("@d", SqlDbType.NVarChar, 12).Value = faddress
            cmd2.Parameters.Add("@P", SqlDbType.NVarChar, 12).Value = fphone
            cmd2.Parameters.Add("@g", SqlDbType.NVarChar, 12).Value = fage
            cmd2.Parameters.Add("@dd", SqlDbType.NVarChar, 12).Value = fdate
            sqlConnection12.Open()
            cmd2.ExecuteReader()
            sqlConnection12.Close()
 
            ScriptManager.RegisterStartupScript(Me, [GetType](), "showalert", "alert('Record Inserted Successfully');", True)
            BindGrid()
        End If
    End If