Fire event on enter key press for a textbox

ASPX:

 <asp:TextBox ID="TextBox1" clientidmode="Static" runat="server" onkeypress="return EnterEvent(event)"></asp:TextBox>    
 <asp:Button ID="Button1" runat="server" style="display:none" Text="Button" />  

JS:
 

 function EnterEvent(e) {  
     if (e.keyCode == 13) {  
       __doPostBack('<%=Button1.UniqueId%>', "");  
     }  
   }  

CS:

 protected void Button1_Click1(object sender, EventArgs e)  
   {  
   }