<script language="javascript" type="text/javascript" >
/**
 * Check email format
 */
function emailCheck(obj, labelName) {
	var objName = eval("document.all."+obj);
	var pattern = /^([\.a-zA-Z0-9_-])+@([a-zA-Z0-9_-])+(\.[a-zA-Z0-9_-])+/;
	if (!pattern.test(objName.value)) {
		alert("请输入正确的邮箱地址。");
		objName.focus();
		return false;
	}
	return true;
}
</script>


email：<input type="text" id="email" name="email" maxlength="30" onblur="return emailCheck('email', 'email')" style="text-align: left; width:300px;" />