easyui datagrid的行编辑器editor 如何实现新增时可修改，编辑时，不可修改

 <table  id="gridlist" data-bind="datagrid:grid" > 
    <thead>  
        <tr>  
            <th field="ck" checkbox="true"  readOnly:true ></th>        
            <th field="OptimisticLockField"  hidden="true"></th> 
            <th field="UserCode"        sortable="true" align="left"    width="80"   editor="{type:‘validatebox‘,options:{required: true }}" >用户名   </th>  
            <th field="UserName"        sortable="true" align="left"    width="200"    editor="{type:‘validatebox‘,options:{required: true }}" >名称   </th> 
            <th field="OriginalPassword" sortable="true" align="left"    width="200"    >密码 </th>
            <th field="Org"             sortable="true" align="left"    width="200" editor="{type:‘lookup‘,options:{required:true,lookupType:‘cloud.PcsOrg‘,window:{title:‘所属机构‘},queryParams:{State:9,Ou:false}}}" formatter="formatOrg" >所属机构 </th>
            <th field="IsEnable"        sortable="true" align="center"    width="120" editor="{type:‘checkbox‘,options:{on:1,off:0}}" formatter="com.formatCheckbox" >是否可用</th>
            <th field="IsAdmin"         align="center"  width="120"        editor="{type:‘checkbox‘,options:{on:1,off:0}}" formatter="com.formatCheckbox">是否管理员</th>
            <th field="LoginCount"      sortable="true" align="right"    width="120"  >登录次数</th>
            <th field="LastLoginDate"   sortable="true" align="left"    width="135"  formatter="com.formatDate">最后登录日期</th>
            <th field="LastLoginOU"     align="left"  width="170" hidden="true"  >最后登录组织</th>
            <th field="OrganizeNames" align="left" width="170">最后登录组织</th>
            <th field="Permit"          align="center"  width="320" formatter="formatterButton"> 操作     </th> 
            <th field="Description"     align="left"  width="150"  editor="text">描述</th>

        </tr>                            
    </thead>      
</table>

 //原先编辑方法
    this.editClick = function () {
        if (self.RowsCount() > 1) return;
        var row = self.grid.datagrid(‘getSelected‘);
        if (row == null) {
             com.message(‘error‘, "请选中需编辑的一行数据");
            return;
        }
        var index = self.grid.datagrid(‘getRowIndex‘, row);
        self.gridEdit.begin(index, row);
        self.viewType = v_edit;
        self.IsViewType(v_edit);
    };

    //新的编辑方法
    this.editClick = function () {
        if (self.RowsCount() > 1) return;
        var row = self.grid.datagrid(‘getSelected‘);
        if (row == null) {
             com.message(‘error‘, "请选中需编辑的一行数据");
            return;
        }
        //在编辑后把用户名改为查看状态
        if (row._isnew == undefined) {
            //编辑的时候把用户名改为查看状态
            $(‘#gridlist‘).datagrid(‘removeEditor‘, ‘UserCode‘);
        }
        var index = self.grid.datagrid(‘getRowIndex‘, row);
        self.gridEdit.begin(index, row);
        self.viewType = v_edit;
        self.IsViewType(v_edit);
    };