Struts2的josn插件 josn-plugin 對我們開發extjs程序很方便,但是他每次返回的數據格式都是以一個對象的方式返回的,對象中可以包含其他格式的數據,比如數組.
這就是一般的返回格式
Js代碼
{"root":[{"address":"shenzhen","company":"Bank of China","manager":"true","name":"Jack","password":"a","userid":"8ad08c8323eeb3ba0123eeb3c6e20001","username":"a","zip":"518000"},{"address":"dongjing","company":"Bank of Japan","manager":"false","name":"Jack Cheng","password":"b","userid":"8ad08c8323eeb3ba0123eeb3c6e20002","username":"b","zip":"518000"}],"totalProperty":2}
struts2後台配置為
Xml代碼
<action name="getUsers" class="userAction" method="getUsers">
<result type="json">
<param name="root">
page
</param>
<param name="excludeNullProperties">
true
</param>
<param name="includeProperties">
root.*,totalProperty
</param>
</result>
</action>
而我們做樹(TreePanel)的時候需要服務器返回的數據是數組對象的形式.如下
Js代碼
[{"address":"shenzhen","company":"Bank of China","manager":"true","name":"Jack","password":"a","userid":"8ad08c8323eeb3ba0123eeb3c6e20001","username":"a","zip":"518000"},{"address":"dongjing","company":"Bank of Japan","manager":"false","name":"Jack Cheng","password":"b","userid":"8ad08c8323eeb3ba0123eeb3c6e20002","username":"b","zip":"518000"}]
但是json-plugin不支持直接返回這種格式,所以我們可以修改一下TreeLoader的處理函數
Js代碼
//TreeLoader擴展,支持josn-plugin返回的json對象中包含的數組值
Ext.tree.JsonPluginTreeLoader = function (config) {
this.rootName = 'root';
Ext.tree.JsonPluginTreeLoader.superclass.constructor.call(this, config);
}
Ext.extend(Ext.tree.JsonPluginTreeLoader, Ext.tree.TreeLoader, {
processResponse: function (response, node, callback) {
var json = response.responseText;
try {
var o = response.responseData || Ext.decode(json);
//在原代碼基礎上增加了下面處理---------------------
if (Ext.type(o) == 'object') {//如果返回的是對象則獲取他的root部分,rootName是可以在使用的時候配置的
o = o[this.rootName || 'root'];
}
//--------------------------------------------------
node.beginUpdate();
for (var i = 0, len = o.length; i < len; i++) {
var n = this.createNode(o[i]);
if (n) {
node.appendChild(n);
}
}
node.endUpdate();
this.runCallback(callback, scope || node, [node]);
} catch(e) {
this.handleFailure(response);
}
}
});
使用方法
Js代碼
{
xtype: 'treepanel',
loader: new Ext.tree.JsonPluginTreeLoader({
dataUrl: 'xxx.action'
//rootName:'nodes' //這裡可以動態配置,已配合服務器返回的數組名稱:)
}),
root: new Ext.tree.AsyncTreeNode({
text: '根節點'
})
}
後台struts2的josn配置如下
Xml代碼
<action name="getUsers" class="userAction" method="getUsers">
<result type="json">
<param name="root">
page
</param>
<param name="excludeNullProperties">
true
</param>
<param name="includeProperties">
root.*
</param>
</result>
