Jquery 网格单元中jqwidget dropdownlist的数据库绑定

在jqwidget网格示例中（在jqxGrid左菜单下，打开编辑/编辑），数据在客户端生成。如何将dropdownlist绑定到asp.net MVC3项目中的数据库？（您可以在“演示”选项卡中的“产品”列下查看dropdownlist）

您可以使用名为“createeditor”的函数在内部初始化dropdownlist

列定义：

{ text: 'Proyecto', columntype: 'dropdownlist', datafield: 'jobid', width: 10,
                      createeditor: function (row, cellvalue, editor) {
                          editor.jqxDropDownList({ displayMember: 'displaylabel', valueMember: 'catalogvalue', source: dropdownListAdapter });
                      }
}

DropDownList的数据适配器可以使用类似的代码进行初始化：

source = {
    datatype: "xml",
    datafields: [
    { name: 'CompanyName' },
    { name: 'ContactName' },
    { name: 'ContactTitle' },
    { name: 'City' },
    { name: 'Country' },
    { name: 'Address' }
    ],
    async: false,
    record: 'Table',
    url: 'Default.aspx/GetCustomers',
};
var dropdownListAdapter = new $.jqx.dataAdapter(source,
    {  contentType: 'application/json; charset=utf-8'}
);   

---

使用数据库初始化dropdownlist时，应该将其绑定到datasource（或dataadapter），并设置selectedIndex。然后，对于行更新，所选值应保持在select上

列定义可能类似于：

{ text: 'Urun', columntype: 'dropdownlist', datafield: 'UrunAdi', width: 177,
                  initeditor: function (row, cellvalue, editor) {
                      var urunId = $('#jqxgrid').jqxGrid('getcellvalue', row, "UrunId");
                      editor.jqxDropDownList({ displayMember: 'UrunAdi', source: dropdownListAdapter, selectedIndex: urunId });
                      $(document).on('select', editor, function (event) {
                          selectedUrunId = editor.jqxDropDownList('getSelectedIndex');
                      });
                  }
}

变量“selectedrunid”应该全局定义，可能类似于

var selectedrunid=-1在jqxgrid初始化之前。然后在updaterow定义中（在源定义中），应该使用下拉列表的选定值。可能是这样的：

if (selectedUrunId != undefined && selectedUrunId != -1) {
                    rowdata.UrunId = selectedUrunId;
                    selectedUrunId = -1;
                }

此场景的总体场景为：

        // prepare the data
        var gridSource = {
            datatype: "json",
            datafields: [{ name: 'KargoId' }, { name: 'UrunAdi' }, { name: 'UrunId', type: 'int' }],
            url: 'BindGrid',
            updaterow: function (rowid, rowdata) {
                // synchronize with the server - send update command  
                if (selectedUrunId != undefined && selectedUrunId != -1) {
                    rowdata.UrunId = selectedUrunId;
                    selectedUrunId = -1;
                }                   

                var data = $.param(rowdata);

                $.ajax({
                    dataType: 'json',
                    url: 'UpdateEditGrid',
                    data: data,
                    success: function (data, status, xhr) {
                        gridDataAdapter.dataBind();                            
                    },
                    error: function (xhr, status, error) {
                        alert(JSON.stringify(xhr));
                    }
                });
            }
        };

        var gridDataAdapter = new $.jqx.dataAdapter(gridSource);

        var dropdownSource = {
            datatype: "json",
            datafields: [{ name: 'UrunId' }, { name: 'UrunAdi'}],
            url: 'BindDropdown'
        };

        var selectedUrunId = -1;
        var dropdownListAdapter = new $.jqx.dataAdapter(dropdownSource);

        // initialize jqxGrid
        $("#jqxgrid").jqxGrid(
        {
            width: 670,
            source: gridDataAdapter,
            editable: true,
            theme: theme,
            selectionmode: 'singlecell',
            columns: [
              { text: '#', datafield: 'KargoId', width: 40 },                  
              { text: 'Urun', columntype: 'dropdownlist', datafield: 'UrunAdi', width: 177,
                  initeditor: function (row, cellvalue, editor) {
                      var urunId = $('#jqxgrid').jqxGrid('getcellvalue', row, "UrunId");
                      editor.jqxDropDownList({ displayMember: 'UrunAdi', source: dropdownListAdapter, selectedIndex: urunId });
                      $(document).on('select', editor, function (event) {
                          selectedUrunId = editor.jqxDropDownList('getSelectedIndex');
                      });
                  }
              }]
        });

最初valueMember出现（数字出现，而不是文本）；然后，如果您尝试选择另一项，您可以看到下拉列表的displayMember文本。另一个问题是，若您尝试更新，错误的id值（或错误的valueMember）将进入服务器。