Check in your code with the sample below:
This goes in html content or .aspx
<asp:Button ID="cmdGet" runat="server" Text="View" CssClass="uiButton" OnClick="cmdGet_Click" Height="21px" Width="50px" />
This goes in code behind or .cs
protected void cmdGet_Click(object sender, EventArgs e)
If still you face problem, post your .aspx and .cs code that will help us to understand your problem better if we haven't yet:)
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