Ajax struts2 drop-down box assignment (applicable to all)

1. This Code is applicable to all drop-down lists.
2. All the drop-down lists of a project only need this public method;
Step 1: Create an object bean;
Copy codeThe Code is as follows:
Public class DictionaryBean {
Private String value_Id; // The option id in the drop-down list
Private String value; // The option value in the drop-down list.
Private String flag; // The type of the value corresponding to the drop-down box, for example, flag = 1, the drop-down list shows the province information, and the flag = 2 shows the municipal information;
Public String getValue_Id (){
Return value_Id;
}
Public void setValue_Id (String valueId ){
Value_Id = valueId;
}
Public String getValue (){
Return value;
}
Public void setValue (String value ){
This. value = value;
}
Public String getFlag (){
Return flag;
}
Public void setFlag (String flag ){
This. flag = flag;
}
}

Step 2Write the following method in your action to retrieve listbean. listbean encapsulates bean. valueId and bean. value;
Copy codeThe Code is as follows:
/**
*
* @ Author ZhuangZi
* @ Class com. hzdracom. action. DictionaryAction
* @ Method listDictionary
* @ Directions public method for obtaining the pull-down list information
* @ Date 10:08:39 void
*/
Public void listDictionary (){
String json = "";
Try {
ListDictionary = dictionaryService. handleListDictionary (bean );
Json = JSON. toJSONString (listDictionary); // convert to a json string
HttpServletResponse response = ServletActionContext. getResponse ();
Response. setContentType ("text/html ");
Response. setCharacterEncoding ("UTF-8 ");
PrintWriter out;
Out = response. getWriter ();
Out. println (json );
Out. flush ();
Out. close ();
} Catch (Exception e ){
E. printStackTrace ();
}
}

Sturts. xml configuration information
Copy codeThe Code is as follows:
<Action name = "listDictionary" method = "listDictionary" class = "com. hzdracom. action. DictionaryAction">
</Action>

Step 3Encapsulate public js Code. js file name dictionary. js
Copy codeThe Code is as follows:
/**
* When there are too many threads, there are too many other threads.
* Author: ZhuangZi
* Class Name: public method Initialization
* Function: public method Initialization
* Details: public method Initialization
* Release: 1.0
* Date: 2013-03-22
* Note:
* When there are too many threads, there are too many other threads.
*/
$ (Function (){
/* 1. The value of the drop-down box is always unavailable */
SelectBox ([

Copy codeThe Code is as follows:
{Id _: "# down_type", id: "# downtype", flag: "2 "},
{Id _: "# kuai_flag", id: "# kuaiflag", flag: "3"}]);
// SelectBox {[{id _: "ID of the selected value in your drop-down box", id: "ID of the drop-down box", flag: "Type of the drop-down box value"}]};

Copy codeThe Code is as follows:
// There Is A {id _: "# kuai_flag", id: "# kuaiflag", flag: "3"} such object has a drop-down box information;
});
/**
* When there are too many threads, there are too many other threads.
* Author: ZhuangZi
* Class Name: common method for getting the drop-down box Value
* Function: select a value from the drop-down list.
* Details: load the drop-down list
* Release: 1.0
* Date: 2013-03-22
* Note: if you add a new drop-down box, you need to add an object to the array list.
* Parameter: id _: ID of the selected value in the drop-down box; id: ID of the drop-down box; flag: Type of the value in the drop-down box, that is, the type of the displayed content
* When there are too many threads, there are too many other threads.
*/
Function selectBox (list ){
For (var I = 0, len = list. length; I <len; I ++ ){
(Function (bean ){
Var pageId = $ (bean. id _). val ();
$. Ajax ({
Type: 'post ',
Url: '../dictionary/listDictionary. do ',
Data: 'bean. flag = '+ bean. flag,
DataType: 'json ',
Success: function (json ){
For (var I = 0; I <json. length; I ++ ){
$ (Bean. id). append ("<option value = '"
+ Json [I]. value_Id + "'>"
+ Json [I]. value + "</option> ");
If (pageId! = Null & pageId! = "" & PageId = json [I]. value_Id ){

$ (Bean. id). find ("option"). attr ("selected", true );
}
}
},
Error: function (){
Alert ('error ');
}
});
}) (List [I]);
}
}

Step 4The field information is hidden under the page information, that is, after you select a query item, it will be selected
Introduce js
Copy codeThe Code is as follows:
<Script language = "javascript1.2" src = "<s: url value ="/js/jquery. js "includeParams =" false "/>"> </script>
<Script language = "javascript1.2" src = "<s: url value ="/js/dictionary. js "includeParams =" false "/>"> </script>

Copy codeThe Code is as follows:
<S: hidden id = "down_type" name = "yhaoPortalsDownBean. downType"/>
<Td width = "25%" height = "33" class = "addtabletd1"> download type ID: </td>
<Td width = "25%" height = "33" class = "addtabletd2">
<Select id = "downtype" name = "yhaoPortalsDownBean. downType" class = "textfrom" class = "width: 120">
<Option value = ""> --- all --- </option>
</Select>
</Td>

Step 5Additional information: Method in dao. The flag used in the following method is the value passed by the flag in js.
Copy codeThe Code is as follows:
Public List <DictionaryBean> handleListDictionary (DictionaryBean bean) throws DataAccessException, Exception {
List <DictionaryBean> list = new ArrayList <DictionaryBean> ();
Try {
String SQL = "";
/* Get the page drop-down list */
If (bean. getFlag (). equals ("1 ")){
SQL = "SELECT PAGE_FLAG VALUE_ID, PAGE_NAME VALUE FROM YHAO_PORTALS_PAGE ";
}
/* Get the download type icon drop-down list */
If (bean. getFlag (). equals ("2 ")){
SQL = "SELECT DOWNTYPE_FLAG VALUE_ID, DOWNTYPE_NAME VALUE FROM YHAO_PORTALS_DOWNTYPE ";
}
/* Get the block ID drop-down list */
If (bean. getFlag (). equals ("3 ")){
SQL = "SELECT KUAI_FLAG VALUE_ID, KUAI_NAME VALUE FROM YHAO_PORTALS_KUAI ";
}
List = this. query (SQL, new DictionaryList ());
} Catch (Exception e ){
E. printStackTrace ();
}
Return list;
}

All done.