Delphi使用JSON解析调用淘宝IP地址库REST API 示例

淘宝IP地址库：http://ip.taobao.com，里面有REST API 说明。

Delphi XE 调试通过，关键代码如下：

var
  IdHTTP: TIdHTTP;
  RequestURL: string;
  ResponseStream: TStringStream;
  JO, JData: TJSONObject;
begin
  IdHTTP := TIdHTTP.Create(nil);
  IdHTTP.ReadTimeout := 0;
  IdHTTP.AllowCookies := True;
  IdHTTP.ProxyParams.BasicAuthentication := False;
  IdHTTP.ProxyParams.ProxyPort := 0;
  IdHTTP.Request.ContentLength := -1;
  IdHTTP.Request.ContentRangeEnd := 0;
  IdHTTP.Request.ContentRangeStart := 0;
  IdHTTP.Request.ContentType := 'application/x-www-form-urlencoded';
  IdHTTP.Request.Accept := 'text/html, */*';
  IdHTTP.Request.BasicAuthentication := False;
  IdHTTP.Request.UserAgent := 'Mozilla/3.0 (compatible; Indy Library)';
  IdHTTP.HTTPOptions := [hoForceEncodeParams];
  RequestURL := 'http://ip.taobao.com/service/getIpInfo.php?ip=' + edtIP.Text;
  ResponseStream := TStringStream.Create;
  IdHTTP.Get(RequestURL, ResponseStream);
  IdHTTP.Free;
  ResponseStream.Position := 0;
  Memo1.Text := ResponseStream.DataString;
  ResponseStream.Position := 0;
  JO := TJSONObject.ParseJSONValue(ResponseStream.DataString) as TJSONObject;
  JData := JO.Get('data').JsonValue as TJSONObject;
  leISP.Text := (JData.Get('isp').JsonValue as TJSONString).Value;
  leCountry.Text := (JData.Get('country').JsonValue as TJSONString).Value;
  leArea.Text := (JData.Get('area').JsonValue as TJSONString).Value;
  leRegion.Text := (JData.Get('region').JsonValue as TJSONString).Value;
  leCity.Text := (JData.Get('city').JsonValue as TJSONString).Value;
  JO.Free;
  ResponseStream.Free;
end;