exths combo 选择问题

Question

初学extjs，combo的datastore如果为SimpleStore是，下拉选择正常，
如果把datastore换成hpptProxy，可以下来所有数据，但单击选择时只不管我选择哪个值只能得到第一条数据值，
datastore的valueField是不同的，
界面如下：
json返回的数据如下：
{totalCount:11,success:true,error:"",singleInfo:"",data:[{"DisplayField":"河南1","ValueyField":"河南1"},{"DisplayField":"河南11","ValueyField":"河南11"},{"DisplayField":"河南2","ValueyField":"河南2"},{"DisplayField":"河南3","ValueyField":"河南3"},{"DisplayField":"河南4","ValueyField":"河南4"},{"DisplayField":"河南5","ValueyField":"河南5"},{"DisplayField":"河南8","ValueyField":"河南8"},{"DisplayField":"偃师10","ValueyField":"偃师10"},{"DisplayField":"偃师6","ValueyField":"偃师6"},{"DisplayField":"偃师7","ValueyField":"偃师7"},{"DisplayField":"偃师9","ValueyField":"偃师9"}]}js源码：
    var storeRegiPlace = new Ext.data.Store({
        proxy: new Ext.data.HttpProxy //定义读取数据的接口
({
    url: "../URL/EmployeeURL.aspx?op=seleRegiplace"
}),
        reader: new Ext.data.JsonReader //读取的后台数据存储到记data
({
    totalProperty: 'totalCount',
    root: 'data'
}, ['DisplayField', 'ValueFiled'])
    }); //end store
......
items:
{
xtype: "combo",
name: "Regi_place",
id: "Regiplace",
triggerAction: "all",
fieldLabel: "户口",
anchor: "90%",
store: storeRegiPlace,
//pageSize: 10,
minListWidth: 230,
minChars: 4, //reload
displayField: "DisplayField",
valueField: "ValueField",
selectOnFocus: true,
mode: 'remote',
typeAhead: true,
emptyText: '请选择或输入户口所在地'
}请问哪里出问题了呢？

Answer 1

 var typeStores = new Ext.data.Store({
                        url: '<%=Url.Action("LoadTypes", "TypeInfo") %>',
                        reader: new Ext.data.JsonReader({
                            id: 'Id'
                        }, ['Id', 'TypeName']),
                        remoteSort: false
                    });
                    typeStores.load();                    var txtCaseType = new Ext.form.ComboBox({
                     fieldLabel: '<font color="red">*</font>案件类型',
                        store: typeStores,
                        name: 'CaseTypeId',
                        hiddenName: 'CaseTypeId',
                        valueField: 'Id',
                        displayField: 'TypeName',
                        typeAhead: true,
                        mode: 'remote',
                        triggerAction: 'all',
                        emptyText: '---请选择类型---',
                        selectOnFocus: true,
                        allowBlank: false,   
                        width: 200
                    });