Change ASP.Net Label Text based on TextBox value using C# and VB.Net

Hi Indradeo,

Please refer below sample.

HTML

<table>
    <tr>
        <td>Number:<asp:TextBox ID="txtNumber" runat="server" AutoPostBack="true" OnTextChanged="OnTextChanged"></asp:TextBox></td>
    </tr>
    <tr>
        <td>
            <asp:Label ID="lblMessage" runat="server"></asp:Label></td>
    </tr>
</table>

Code

C#

protected void OnTextChanged(object sender, EventArgs e)
{
    int number = int.Parse(txtNumber.Text);
    if (number > 40000000 && number <= 150000000)
    {
        lblMessage.Text = "Services";
    }
    else if (number > 150000000)
    {
        lblMessage.Text = "Purches";
    }
}

VB.Net

Protected Sub OnTextChanged(ByVal sender As Object, ByVal e As EventArgs)
    Dim number As Integer = Integer.Parse(txtNumber.Text)
    If number > 40000000 AndAlso number <= 150000000 Then
        lblMessage.Text = "Services"
    ElseIf number > 150000000 Then
        lblMessage.Text = "Purches"
    End If
End Sub

Screenshot