尝试在JQGrid中使用动态列，但最终得到空网格

Question

我试图找出为什么我的网格正在加载但完全是空的。我只是不确定我错过了什么或做错了什么。

以下是JSON

的示例

{
"columns": [
    {
        "name": "ID",
        "index": "ID",
        "width": "5",
        "align": "center",
        "hidden": "true"
    },
    {
        "name": "WorkRequestID",
        "index": "WorkRequestID",
        "width": "55",
        "align": "center",
        "hidden": "false",
        "sorttype": "int"
    },
    {
        "name": "ProductName",
        "index": "ProductName",
        "width": "70",
        "align": "center",
        "hidden": "false"
    }],
"headers": [
        "ID",
        "WR#",
        "Product Name",
        "Project Name",
        "PL Assigned"]
}

这是网格代码的一部分

    var columns;
    var headers;

    var columnInfo = $.ajax({
        type: "POST",
        url: "ColumnHandler.ashx",
        dataType: "json",
        success: function (data) {
            columns = data.columns;
            headers = data.headers;
        },
        fail: function () {

            alert("Failed to retrieve Columns");
        },
        async: false
    });

    jQuery("#gridlist").jqGrid({
        url: 'PSRHandler.ashx?task=get&display=' + display,
        mtype: 'GET',
        datatype: "json",
        jsonReader: {
            page: "page",
            total: "total",
            records: "records",
            repeatitems: false,
            id: "ID"
        },
        colNames: headers,
        colModel: columns,
        pager: jQuery('#gridpager'),
        rowNum: 8,
        scroll: 1,
        scrollrows: false,
        editurl: 'psrhandler.ashx?task=save',
        gridview: true,
        viewrecords: true,
        loadonce: true,
        ignoreCase: true,
        viewsortcols: [true, 'vertical', true],

就像我上面提到的那样，网格确实出现在页面上没有错误但没有显示列或数据。我会发布一张图片，但我没有足够的声誉点

非常感谢任何帮助。感谢