Display empty GridView with DropDownList and TextBox using C# and VB.Net in ASP.Net

Hi akhter,

Check this example. Now please take its reference and correct your code.

HTML

<asp:GridView ID="gvlevleone" runat="server" AllowSorting="true" AutoGenerateColumns="false" CssClass="active right"
    BorderColor="#FFFF99" GridLines="Horizontal" ShowHeaderWhenEmpty="True" OnRowDataBound="gvlevleone_RowDataBound"
    ShowFooter="True" OnRowCreated="gvlevleone_RowCreated">
    <AlternatingRowStyle CssClass="altrowstyle" />
    <HeaderStyle CssClass="headerstyle" />
    <RowStyle CssClass="rowstyle" />
    <Columns>
        <asp:TemplateField HeaderText="Code">
            <ItemTemplate>
                <asp:TextBox ID="txtcode" runat="server"></asp:TextBox>
            </ItemTemplate>
        </asp:TemplateField>
        <asp:TemplateField HeaderText="Head">
            <ItemTemplate>
                <asp:Label ID="lbfour" runat="server" Visible="false" />
                <asp:DropDownList runat="server" ToolTip="Select" ID="ddlfour" Width="200px">
                </asp:DropDownList>
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>

Namespaces

C#

using System.Data;
using System.Data.SqlClient;

VB.Net

Imports System.Data
Imports System.Data.SqlClient

Code

C#

SqlConnection con = new SqlConnection("Data Source=SERVER1\\SQLEXPRESS;Integrated Security=SSPI;Initial Catalog=WHMS;MultipleActiveResultSets=True;");
protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        DataTable dt = new DataTable();
        dt.Columns.AddRange(new DataColumn[] { new DataColumn("ddlfour", typeof(int)) });
        dt.Rows.Add();
        this.gvlevleone.DataSource = dt;
        this.gvlevleone.DataBind();
    }
}

protected void gvlevleone_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        DropDownList ddlContnam = (DropDownList)e.Row.FindControl("ddlfour");
        SqlCommand cmd = new SqlCommand("select * from Customers ", con);
        SqlDataAdapter sda = new SqlDataAdapter(cmd);
        DataTable dt = new DataTable();

        sda.Fill(dt);
        ddlContnam.DataSource = dt;
        ddlContnam.DataTextField = "Name";
        ddlContnam.DataValueField = "CustomerId";
        ddlContnam.DataBind();

        ddlContnam.Items.Insert(0, new ListItem("--Select Customer--", "0"));
    }
}

protected void gvlevleone_RowCreated(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.EmptyDataRow)
    {
        DropDownList ddl = (DropDownList)e.Row.FindControl("ddlfour");
        if (ddl != null)
        {
            ddl.Items.Add(new ListItem("Select", "0"));
        }
    }
}

VB.Net

Private con As SqlConnection = New SqlConnection("Data Source=SERVER1\\SQLEXPRESS;Integrated Security=SSPI;Initial Catalog=WHMS;MultipleActiveResultSets=True;")
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not IsPostBack Then
        Dim dt As DataTable = New DataTable()
        dt.Columns.AddRange(New DataColumn() {New DataColumn("ddlfour", GetType(Integer))})
        dt.Rows.Add()
        Me.gvlevleone.DataSource = dt
        Me.gvlevleone.DataBind()
    End If
End Sub

Protected Sub gvlevleone_RowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs)
    If e.Row.RowType = DataControlRowType.DataRow Then
        Dim ddlContnam As DropDownList = CType(e.Row.FindControl("ddlfour"), DropDownList)
        Dim cmd As SqlCommand = New SqlCommand("select * from Customers ", con)
        Dim sda As SqlDataAdapter = New SqlDataAdapter(cmd)
        Dim dt As DataTable = New DataTable()
        sda.Fill(dt)
        ddlContnam.DataSource = dt
        ddlContnam.DataTextField = "Name"
        ddlContnam.DataValueField = "CustomerId"
        ddlContnam.DataBind()
        ddlContnam.Items.Insert(0, New ListItem("--Select Customer--", "0"))
    End If
End Sub

Protected Sub gvlevleone_RowCreated(ByVal sender As Object, ByVal e As GridViewRowEventArgs)
    If e.Row.RowType = DataControlRowType.EmptyDataRow Then
        Dim ddl As DropDownList = CType(e.Row.FindControl("ddlfour"), DropDownList)
        If ddl IsNot Nothing Then
            ddl.Items.Add(New ListItem("Select", "0"))
        End If
    End If
End Sub