How to display loading image or text while processing
<p>in my project i am checking links whether its working or not ,when i click on create link button i want to display please wait for while but when and when if their some text in text box1if textbox1.text == null then it should not be display and when its not null then when i will click create button it should show please wait,my code is working but i want to check if their is some value in text box and user click the create button it should show please wait a while .if their no value in textbox1 then if user click on create button then please wait should not be displayed</p>

<p>here is my code</p>

<pre><code>&lt;script type="text/javascript"&gt;       

            function ShowProgressBar() {
                if (Textbox1.Text == " ") {
                    document.getElementById('dvProgressBar').style.visibility = "hidden";
                }
                else {
                    document.getElementById('dvProgressBar').style.visibility = "visible";
                }
            }        
    &lt;/script&gt;

      &lt;asp:Button ID="Button1" runat="server" Text="Create link" OnClick="btn_createlink_Click" OnClientClick="javascript:ShowProgressBar()" /&gt;

    &lt;br /&gt;
        &lt;div ID="dvProgressBar" style="visibility: hidden;"&gt;
        &lt;div id="content" style="text-align: left; " &gt; 
         Please wait for while...
      &lt;/div&gt;
      &lt;/div&gt;

    &lt;asp:TextBox ID="TextBox1" runat="server" TextMode="MultiLine" Height="373px" 
        Width="410px" ViewStateMode="Enabled"&gt;&lt;/asp:TextBox&gt;
</code></pre>
