EasyUI datagrid 多条件查询

<script type="text/javascript">

        $(function () {
            $("#dg").datagrid({
                url: '',
                singleSelect: true,
                pagination: true,
                pageSize: ,
                pageList: [, , , , , , , ],
                queryParams: form2Json("searchform"),　　//关键之处
                //锁定列
            frozenColumns: [[{
                field: 'ck', checkbox: true
            },
        ]],
            columns: [[{
                field: "be_id",
                title: "专家ID",
                hidden: true
            }, {
                field: "be_name",
                title: "专家姓名",
                align: 'left',
                width:
            }, {
                field: "be_post",
                title: "专家职称",
                align: 'left',
                width: 

            }, {
                field: "dt_id",
                title: "所属科室",
                align: 'center',
                width: ,
                formatter: function (value, row) {
                    return formatterDepartment(value)
                }
            }, {
                field: "be_intro",
                title: "专家简介",
                align: 'left',
                width:
            }, {
                field: "be_order",
                title: "排序ID",
                align: 'center',
                width:
            }]],
            })//datagrid

          $("#submit_search").linkbutton({ iconCls: 'icon-search', plain: true })
            .click(function () {
                $('#dg').datagrid({ queryParams: form2Json("searchform") });   //点击搜索
            });

        })

        //将表单数据转为json
        function form2Json(id) {

            var arr = $("#" + id).serializeArray()
            var jsonStr = "";

            jsonStr += '{';
            for (var i = ; i < arr.length; i++) {
                jsonStr += '"' + arr[i].name + '":"' + arr[i].value + '",'
            }
            jsonStr = jsonStr.substring(, (jsonStr.length - ));
            jsonStr += '}'

            var json = JSON.parse(jsonStr)
            return json
        }

    </script>

HTML

<form name="searchform" method="post" action="" id ="searchform">
    <td width="" height=""><strong>专家检索：</strong></td>
    <td height="">
        <input type="text" name="keyword" size= >
        <select name="search_type" id="search_type" >
            <option value="-1">请选择搜索类型</option>
            <option value="be_name" >按专家姓名</option>
            <option value="be_intro">按专家简介</option>
        </select>
        <select name="search_dept" id="search_dept">
            <option value="-1">请选择所属科室</option>
        </select>
        <a id="submit_search">搜索</a>
    </td>
  </form>
  <table id="dg"></table>

queryParams: form2Json("searchform")  是关键，这个属性是专门用来查询的

　　为搜索按钮绑定click事件

$("#submit_search").click(function () {
                $('#dg').datagrid({ queryParams: form2Json("searchform") });   //点击搜索
            });