combox使用要点

<select id="node_type" name="node_type" class="easyui-combobox" required="true">
                        <option value="">根节点</option>
                        <option value="">子节点</option>
</select>

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设置默认值：

　　$("#node_type").combobox('setValue', 1);//设置value

注意：<select required="true"  class="easyui-combobox" name="department_id" style="width:150px;margin-top:10px;"
                                data-options="
                                valueField:'department_id',
                                textField:'department_name',
                                url:'user_manage.aspx?getDep=1'"
                              />

是 　：　　　　　　　　valueField:'department_id',
                                textField:'department_name',

写成　　　　　　　　idField了的话选择列表可以出来，但不能选中