How does Json-lib handle when using Ajax-JS Tutorial-php.cn

This time I will show you how to handle Json-lib when using Ajax. What are the precautions for Json-lib processing when using Ajax? The following is a practical case, let's take a look.

Whether you are using ajax or easyui and other frameworks, the problem of json processing is involved when the background outputs data to the front. Here are two processing methods. The first is to manually configure the json processing method, and the other is to manually configure the json processing method. A solution using json-lib. The ordinary manual configuration method is clumsy. It needs to be configured one by one according to the field name each time, so it cannot be used on other objects, which reduces the reusability of the code. The json-lib tool can be used to achieve automatic processing and different processing for different objects. Measures have greatly improved the processing efficiency and code reusability. The processes of the two methods are introduced below based on cases:

Method 1: Ordinary method, through the process of manual configuration transformation, request with easyui's

Method is an example. The frontend requests user list data from the backend through dategrid. There are ordinary field (int, String) data and date (date) data in the data.

jsp page:

<table id="dg" title="用户管理" class="easyui-datagrid"
 fitColumns="true" pagination="true" rownumbers="true"
 url="${pageContext.request.contextPath}/user_list.action" fit="true" toolbar="#tb">
 <thead>
 <tr>
  <th field="cb" checkbox="true" align="center"></th>
  <th field="id" width="50" align="center">编号</th>
  <th field="trueName" width="80" align="center">真实姓名</th>
  <th field="userName" width="80" align="center">用户名</th>
  <th field="password" width="80" align="center">密码</th>
  <th field="sex" width="50" align="center">性别</th>
  <th field="birthday" width="100" align="center">出生日期</th>
  <th field="identityId" width="130" align="center">身份证</th>
  <th field="email" width="120" align="center">邮件</th>
  <th field="mobile" width="80" align="center">联系电话</th>
  <th field="address" width="100" align="center">家庭地址</th>
 </tr>
 </thead>
</table>

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action layer:

public void list()throws Exception{
 PageBean pageBean=new PageBean(Integer.parseInt(page), Integer.parseInt(rows));
 List<User> userList=userService.findUserList(s_user, pageBean);
 Long total=userService.getUserCount(s_user);
 JSONObject result=new JSONObject();
 JSONArray jsonArray=JsonUtil.formatUserListToJsonArray(userList);
 //easyui接收属性为rows（数据内容）和total（总记录数）
 result.put("rows", jsonArray);
 result.put("total", total);
 //获取response对象
 ResponseUtil.write(ServletActionContext.getResponse(), result);
}

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util tool:

public class JsonUtil {
  /**
   * 将List结果集转化为JsonArray
   * @param gradeService
   * @param stuList
   * @return
   * @throws Exception
   */
  public static JSONArray formatUserListToJsonArray(List<User> userList)throws Exception{
    JSONArray array=new JSONArray();
    for(int i=0;i<userList.size();i++){
      User user=userList.get(i);
      JSONObject jsonObject=new JSONObject(); 
      jsonObject.put("userName", user.getUserName());   //需手动逐个配置json的key-code
      jsonObject.put("password", user.getPassword());
      jsonObject.put("trueName", user.getTrueName());
      jsonObject.put("sex", user.getSex());
      jsonObject.put("birthday", DateUtil.formatDate((user.getBirthday()), "yyyy-MM-dd"));
      jsonObject.put("identityId", user.getIdentityId());
      jsonObject.put("email", user.getEmail());
      jsonObject.put("mobile", user.getMobile());
      jsonObject.put("address", user.getAddress());
      jsonObject.put("id", user.getId());
      array.add(jsonObject);
    }
    return array;
  }
}

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Method 2: Use the jsonLib tool to complete the processing, using the easyui request method For example, the frontend requests product list data from the backend through dategrid. There are ordinary field (int, String) data and date (date) data in the data. At the same time, the product object (Product) is also cascaded with the category object (ProductType)

jsp page:

<table id="dg" title="商品管理" class="easyui-datagrid"
fitColumns="true" pagination="true" rownumbers="true"
 url="${pageContext.request.contextPath}/product_list.action" fit="true" toolbar="#tb">
 <thead>
 <tr>
 <th field="cb" checkbox="true" align="center"></th>
 <th field="id" width="50" align="center" hidden="true">编号</th>
 <th field="proPic" width="60" align="center" formatter="formatProPic">商品图片</th>
 <th field="name" width="150" align="center">商品名称</th>
 <th field="price" width="50" align="center">价格</th>
 <th field="stock" width="50" align="center">库存</th>
 <th field="smallType.id" width="100" align="center" formatter="formatTypeId" hidden="true">所属商品类id</th>
 <th field="smallType.name" width="100" align="center" formatter="formatTypeName">所属商品类</th>
 <th field="description" width="50" align="center" hidden="true">描述</th>
 <th field="hotTime" width="50" align="center" hidden="true">上架时间</th>
 </tr>
 </thead>
</table>

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action layer:

public void list() throws Exception{
 PageBean pageBean=new PageBean(Integer.parseInt(page),Integer.parseInt(rows));
 List<Product> productList=productService.getProducts(s_product, pageBean);
 long total=productService.getProductCount(s_product);
 
 //使用jsonLib工具将list转为json
 JsonConfig jsonConfig=new JsonConfig();
 jsonConfig.setExcludes(new String[]{"orderProductList"}); //非字符串对象不予处理
 jsonConfig.registerJsonValueProcessor(java.util.Date.class, new DateJsonValueProcessor("yyyy-MM-dd")); //处理日期
 jsonConfig.registerJsonValueProcessor(ProductType.class,new ObjectJsonValueProcessor(new String[]{"id","name"}, ProductType.class)); //处理类别list对象
 JSONArray rows=JSONArray.fromObject(productList, jsonConfig);
 JSONObject result=new JSONObject();
 result.put("rows", rows);
 result.put("total", total);
 ResponseUtil.write(ServletActionContext.getResponse(), result);
}

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util tool:

/**
 * json-lib 日期处理类
 * @author Administrator
 *
 */
public class DateJsonValueProcessor implements JsonValueProcessor{
 private String format; 
 
  public DateJsonValueProcessor(String format){ 
    this.format = format; 
  } 
 public Object processArrayValue(Object value, JsonConfig jsonConfig) {
 // TODO Auto-generated method stub
 return null;
 }
 public Object processObjectValue(String key, Object value, JsonConfig jsonConfig) {
 if(value == null) 
    { 
      return ""; 
    } 
    if(value instanceof java.sql.Timestamp) 
    { 
      String str = new SimpleDateFormat(format).format((java.sql.Timestamp)value); 
      return str; 
    } 
    if (value instanceof java.util.Date) 
    { 
      String str = new SimpleDateFormat(format).format((java.util.Date) value); 
      return str; 
    } 
    return value.toString(); 
 }
}
/**
 * 解决对象级联问题
 * @author Administrator
 *
 */
public class ObjectJsonValueProcessor implements JsonValueProcessor{
 /**
 * 保留的字段
 */
 private String[] properties; 
 
 /**
 * 处理类型
 */
 private Class<?> clazz; 
 
 /**
 * 构造方法 
 * @param properties
 * @param clazz
 */
 public ObjectJsonValueProcessor(String[] properties,Class<?> clazz){ 
    this.properties = properties; 
    this.clazz =clazz; 
  } 
 
 public Object processArrayValue(Object arg0, JsonConfig arg1) {
 // TODO Auto-generated method stub
 return null;
 }
 public Object processObjectValue(String key, Object value, JsonConfig jsonConfig) {
 PropertyDescriptor pd = null; 
    Method method = null; 
    StringBuffer json = new StringBuffer("{"); 
    try{ 
      for(int i=0;i<properties.length;i++){ 
        pd = new PropertyDescriptor(properties[i], clazz); 
        method = pd.getReadMethod(); 
        String v = String.valueOf(method.invoke(value)); 
        json.append("'"+properties[i]+"':'"+v+"'"); 
        json.append(i != properties.length-1?",":""); 
      } 
      json.append("}"); 
    }catch (Exception e) { 
      e.printStackTrace(); 
    } 
    return JSONObject.fromObject(json.toString()); 
 }
}

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I believe I saw it You have mastered the method in the case of this article. For more exciting information, please pay attention to other related articles on the php Chinese website!