Join two TextBox value and display in another using C# and VB.Net in ASP.Net

Hi indradeo,

Use Substring function to get the first lettor from Name and concadinate with No TextBox to get the desired result.

Check the below sample.

HTML

Emp.No.:<asp:TextBox runat="server" ID="txtNo" AutoPostBack="true" OnTextChanged="OnJoin" />
<br />
Name:<asp:TextBox runat="server" ID="txtName" AutoPostBack="true" OnTextChanged="OnJoin" />
<br />
<asp:TextBox runat="server" ID="txtResult" />

Code

C#

protected void OnJoin(object sender, EventArgs e)
{
    if (!string.IsNullOrEmpty(txtNo.Text.Trim()) && !string.IsNullOrEmpty(txtName.Text.Trim()))
    {
        txtResult.Text = txtName.Text.Trim().Substring(0, 1) + txtNo.Text.Trim();
    }
}

VB.Net

Protected Sub OnJoin(ByVal sender As Object, ByVal e As EventArgs)
    If Not String.IsNullOrEmpty(txtNo.Text.Trim()) AndAlso Not String.IsNullOrEmpty(txtName.Text.Trim()) Then
        txtResult.Text = txtName.Text.Trim().Substring(0, 1) + txtNo.Text.Trim()
    End If
End Sub