JS实现给页面表单设置触发默认按钮

var defaultBtnId;
function setDefaultButton(id) {
defaultBtnId = id;
}
document.onkeydown = function (e) {
var theEvent = window.event || e;
var code = theEvent.keyCode || theEvent.which;
if (code == 13) {
if (typeof (defaultBtnId) != "undefined" && defaultBtnId != null) {
$(":input[id$='" + defaultBtnId + "'].OperationButton").click();
if (typeof (window.event) != "undefined") {
window.event.returnValue = false;
}
}
}
}

<div class="border" onclick="setDefaultButton('SearchButton')">
<table class="noborder">
<tr>
<td class="label">
<asp:Label runat="server" ID="EmployeeIdTitleLabel" Text="Employee ID"></asp:Label><em>*</em>
</td>
<td>
<asp:TextBox runat="server" ID="EmployeeIdTextBox" CssClass="RequiredText" MaxLength="6"
SkinID="IntegerRequired" Width="60px"></asp:TextBox>
<asp:RequiredFieldValidator ID="EmployeeIdTextBoxRequiredFieldValidator" runat="server"
ControlToValidate="EmployeeIdTextBox" ValidationGroup="Search" ErrorMessage="[Employee ID] is required, please re-input."
Display="None"></asp:RequiredFieldValidator>
</td>
<td>
<asp:Button runat="server" SkinID="OperationButton" Text="Search" OnClick="SearchButton_Click"
OnClientClick="return CallValidate('Search');" ID="SearchButton" ValidationGroup="Search"
CommandName="Search" />
</td>
</tr>
</table>
</div>