1.js中封装代码：

 $.fn.serializeObject = function() {
			var o = {};
			var a = this.serializeArray();
			$.each(a, function() {
				if (o[this.name]) {
					if (!o[this.name].push) {
						o[this.name] = [ o[this.name] ];
					}
					o[this.name].push(this.value || '');
				} else {
					o[this.name] = this.value || '';
				}
			});
			return o;
		};

2.js调用方法：

//.loginForm换成你自己的选择器
jsonObj = $(".loginForm").serializeObject(); // json对象
var username = jsonObj.username;
	...

3.html代码示例为（每个字段必须有name）：

<form method="post" class="loginForm">
			<div class="form-group">
				<div class="input-group">
					<div class="input-group-addon">
						<i class="fa fa-user fa-fw"></i>
					</div>
					<input class="form-control" type="text" placeholder="用户名"
						id="username" name="username" minlength="2" autocomplete="off">
				</div>
			</div>
			<div class="form-group">
				<div class="input-group">
					<div class="input-group-addon">
						<i class="fa fa-desktop fa-fw"></i>
					</div>
					<input class="form-control" type="password" placeholder="密码"
						minlength="5" id="password" name="password">
				</div>
			</div>
			<button type="submit" class="btn btn-primary">登录系统</button>
		</form>