我是
JSON的新手,我手上有这个项目,需要我解析JSON并在ListView中显示一些内容.问题是我现在阅读的文档涉及包含JSON数组的JSON对象,而我的案例涉及处理嵌套对象.为了简化故事,下面是总结：我正在使用Delphi XE2与DBXJSON.我向服务器发布了一些值,并且回复了一个如下所示的JSON对象：
{
"products": {
"Men's Sneakers": {
"instock": false,"size": "423","manufacturer": "Adidas","lastcheck": "20120529"
},"Purse": {
"instock": true,"size": "not applicable","manufacturer": "Prada","lastcheck": "20120528"
},"Men's Hood": {
"instock": false,"size": "M","manufacturer": "Generic","lastcheck": "20120529"
}
},"total": 41,"available": 30
}
我想要实现的是将每个项目(即钱包)解析并添加为列表视图中的标题,以及一个子项(制造商).我创建了一个将JSON字符串作为参数的过程,创建了JSON对象,但我不知道如何进一步解析嵌套对象.
procedure TForm1.ParseString(const AString: string);
var
json : TJSONObject;
jPair : TJSONPair;
jValue : TJSONValue;
jcValue : TJSONValue;
l,i : Integer;
begin
json := TJSONObject.ParseJSONValue(TEncoding.ASCII.GetBytes(AString),0) as TJSONObject;
try
//get the pair to evaluate in this case the index is 1
jPair := json.Get(1);
{further process the nested objects and adding them to the listview}
finally
json.Free;
end;
end;
任何建议将被高度赞赏.失去了相当一段时间,试图让Delphi中的JSON和内存无效.
谢谢,
斯芬克斯
解决方法
尝试这个样品
{$APPTYPE CONSOLE}
{$R *.res}
uses
DBXJSON,System.SysUtils;
Const
StrJson=
'{'+
' "products": {'+
' "Men''s Sneakers": {'+
' "instock": false,'+
' "size": "423",'+
' "manufacturer": "Adidas",'+
' "lastcheck": "20120529"'+
' },'+
' "Purse": {'+
' "instock": true,'+
' "size": "not applicable",'+
' "manufacturer": "Prada",'+
' "lastcheck": "20120528"'+
' },'+
' "Men''s Hood": {'+
' "instock": false,'+
' "size": "M",'+
' "manufacturer": "Generic",'+
' "lastcheck": "20120529"'+
' }'+
' },'+
' "total": 41,'+
' "available": 30'+
'}';
procedure ParseJson;
var
LJsonObj : TJSONObject;
LJPair : TJSONPair;
LProducts : TJSONValue;
LProduct : TJSONValue;
LItem : TJSONValue;
LIndex : Integer;
LSize : Integer;
begin
LJsonObj := TJSONObject.ParseJSONValue(TEncoding.ASCII.GetBytes(StrJson),0) as TJSONObject;
try
LProducts:=LJsonObj.Get('products').JsonValue;
LSize:=TJSONArray(LProducts).Size;
for LIndex:=0 to LSize-1 do
begin
LProduct := TJSONArray(LProducts).Get(LIndex);
LJPair := TJSONPair(LProduct);
Writeln(Format('Product Name %s',[LJPair.JsonString.Value]));
for LItem in TJSONArray(LJPair.JsonValue) do
begin
if TJSONPair(LItem).JsonValue is TJSONFalse then
Writeln(Format(' %s : %s',[TJSONPair(LItem).JsonString.Value,'false']))
else
if TJSONPair(LItem).JsonValue is TJSONTrue then
Writeln(Format(' %s : %s','true']))
else
Writeln(Format(' %s : %s',TJSONPair(LItem).JsonValue.Value]));
end;
end;
finally
LJsonObj.Free;
end;
end;
begin
try
ParseJson;
except
on E: Exception do
Writeln(E.ClassName,': ',E.Message);
end;
Readln;
end.
这将返回
Product Name Men's Sneakers instock : false size : 423 manufacturer : Adidas lastcheck : 20120529 Product Name Purse instock : true size : not applicable manufacturer : Prada lastcheck : 20120528 Product Name Men's Hood instock : false size : M manufacturer : Generic lastcheck : 20120529