Reputation: 81
I am trying to implement validations on textbox like if null then display a message to fill the empty field and to check the length of the text entered. I have written the code for it inside TextBox_TextChanged event but it's not working. The event is not getting fired and the user can is able to signup without a username, that is my problem at the moment. Do I have to trigger the event manually? Here is a glimpse of what I am doing:
protected void FirstN_TextBox_TextChanged(object sender, EventArgs e)
{
String firstNameEntered = FirstN_TextBox.Text;
if (firstNameEntered != null)
{
if (firstNameEntered.Length <= 20)
{
MessageBox.Show("Inside text box");
}
else
{
}
}
else
{
FirstN_TextBox.Focus();
MessageBox.Show("Please fill the marked field");
}
Upvotes: 1
Views: 484
Reputation: 4191
change it like this:
From:
<asp:TextBox ID="FirstN_TextBox" placeholder="First name" runat="server" Width="225px" OnTextChanged="FirstN_TextBox_TextChanged"></asp:TextBox>
To:
<asp:TextBox ID="FirstN_TextBox" placeholder="First name" runat="server" Width="225px" OnTextChanged="FirstN_TextBox_TextChanged" AutoPostBack ="true"></asp:TextBox>
Upvotes: 2