Insert record in DataTable if not exist using C# and VB.Net in ASP.Net

Hi ifblipika,

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

HTML

<table border="0" cellpadding="0" cellspacing="0">
    <tr>
        <td>
            Name:&nbsp;<asp:TextBox runat="server" ID="txtName" />
        </td>
    </tr>
    <tr>
        <td>
            Country:&nbsp;<asp:TextBox runat="server" ID="txtCountry" />
        </td>
    </tr>
</table>
<br />
<asp:Button Text="Add" OnClick="Add" runat="server" />
<br />
<br />
<asp:GridView runat="server" ID="gvCustomers" />

Namespaces

C#

using System.Data;

VB.Net

Imports System.Data

Code

C#

protected void Add(object sender, EventArgs e)
{
    DataTable dt = new DataTable();
    dt.Columns.AddRange(new DataColumn[3] { new DataColumn("Id", typeof(int)),
                        new DataColumn("Name", typeof(string)),
                        new DataColumn("Country",typeof(string)) });
    dt.Rows.Add(1, "John Hammond", "United States");
    dt.Rows.Add(2, "Mudassar Khan", "India");
    dt.Rows.Add(3, "Suzanne Mathews", "France");
    dt.Rows.Add(4, "Robert Schidner", "Russia");

    string name = txtName.Text;
    string country = txtCountry.Text;
    if (!string.IsNullOrEmpty(name) && !string.IsNullOrEmpty(country))
    {
        DataRow[] rows = dt.Select("Name='" + name + "' AND Country='" + country + "'");
        if (rows.Length == 0)
        {
            dt.Rows.Add(dt.Rows.Count + 1, name, country);
        }
    }

    gvCustomers.DataSource = dt;
    gvCustomers.DataBind();
}

VB.Net

Protected Sub Add(ByVal sender As Object, ByVal e As EventArgs)
    Dim dt As DataTable = New DataTable()
    dt.Columns.AddRange(New DataColumn(2) {New DataColumn("Id", GetType(Integer)),
                                           New DataColumn("Name", GetType(String)),
                                           New DataColumn("Country", GetType(String))})
    dt.Rows.Add(1, "John Hammond", "United States")
    dt.Rows.Add(2, "Mudassar Khan", "India")
    dt.Rows.Add(3, "Suzanne Mathews", "France")
    dt.Rows.Add(4, "Robert Schidner", "Russia")
    Dim name As String = txtName.Text
    Dim country As String = txtCountry.Text

    If Not String.IsNullOrEmpty(name) AndAlso Not String.IsNullOrEmpty(country) Then
        Dim rows As DataRow() = dt.Select("Name='" & name & "' AND Country='" & country & "'")

        If rows.Length = 0 Then
            dt.Rows.Add(dt.Rows.Count + 1, name, country)
        End If
    End If

    gvCustomers.DataSource = dt
    gvCustomers.DataBind()
End Sub

Screenshot