CODEWITHSUNDEEP
asp.netajax
Zhenia
Zhenia

Reputation: 4179

Incomprehension in asp.net

I want when I click button my textbox1 must change, but textbox3 not Why does not it work?

        protected void Page_Load(object sender, EventArgs e)
        {
            TextBox3.Text = DateTime.Now.ToLongTimeString();
        }

        protected void Button1_Click(object sender, EventArgs e)
        {
            TextBox1.Text = DateTime.Now.ToLongTimeString();
        }

<asp:ScriptManager ID="ScriptManager1" runat="server">
        </asp:ScriptManager>

        <asp:UpdatePanel ID="UpdatePanel1" runat="server">
            <ContentTemplate>
          <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Button"/>
          <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>  
             </ContentTemplate>
    <br />
<asp:TextBox ID="TextBox3" runat="server"></asp:TextBox>
        </asp:UpdatePanel>

When I Click Button1 my TextBox3 changes Why?

Upvotes: 0

Views: 21

Answers (1)

Grant Thomas
Grant Thomas

Reputation: 45058

Because when you click the button you submit a request to the server, which results in a round-trip, which results in Page_Load being executed again. You can avoid this by detecting whether the request is part of the postback cycle using the IsPostBack property:

if (IsPostBack) {

}

Or, as is in most cases, doing stuff when it's not a postback:

if (!IsPostBack) {
  TextBox3.Text = DateTime.Now.ToLongTimeString();
}

Upvotes: 3

Related Questions