search button + gridview
<p>I have a gridview which shows all the information of the data table. I have a textbox and a button. If I want to search some particular files in the gridview, I need to enter the filename in textbox and hit search button. I'm taking care of this with the code</p>

<pre><code>// don't copy and paste this; it is vulnerable to sql injection attacks
SqlDataSource1.SelectCommand = 
    "select * from Table1 where FileName like '%" + TextBox1.Text + "%'"  ;
SqlDataSource1.DataBind();
</code></pre>

<p>I want to display the message like "file not found" if there are no search results. How can I do that?</p>
