<script>
	$(function(){
	function CheckLen(val, msg, min, max){
		val = $.trim(val);
		var len = val.length;
		if(len<min || len>max){
			alert(msg);	
			return false;
		}
		else
			return true;
	}
	
	//电子邮箱验证
	function CheckEmail(email){
		 var pattern = /^([a-zA-Z0-9._-])+@([a-zA-Z0-9_-])+(\.[a-zA-Z0-9_-])+/; 
		 flag = pattern.test(email); 
		 if(!flag){ 
		  	alert("Incorrect email format!"); 
		  	return false; 
		 }else{
		 	return (true); 
		 }
	}
	
	$("#btn_login").click(function(){
		var bval = true;
		var emal = $("#username").val();
		bval = bval && CheckLen(emal, "Input The Email!!!", 3, 100);
		bval = bval && CheckEmail(emal);
		bval = bval && CheckLen($("#password").val(), "Input The PassWord!!!", 5, 20);
		
		return bval;
	});
	
	$("#btn_clear").click(function(){
		$("#username").val('');
		$("#password").val('');
	});
});
</script>