delphi - 带有 Unicode 参数的 C++ Builder TRESTRequest

Question

我正在使用 TRESTRequest 从服务器获取数据。我需要用 Unicode 字符串值填充参数："ôpen"。但是，使用此 Unicode 字符串作为查询参数调用 Execute 时出现崩溃。

我的代码：

    RESTRequest->ResetToDefaults();
    RESTRequest->AddParameter("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8 ", TRESTRequestParameterKind::pkHTTPHEADER);
    //  Get Indexing Status
    RESTRequest->Resource = "XXX/collection1"+ Form1->teReuqestHandler->Text+"?";
    RESTRequest->Method = rmGET;
    // replace all space in name field with '\ '
    UnicodeString lcQuery = Form1->teQuery->Text; // this value should be support french language or ...
    // Body
    RESTRequest->AddParameter("q",lcQuery, TRESTRequestParameterKind::pkGETorPOST);
    // Run
    String str1 = RESTRequest->GetFullRequestURL();
    RESTRequest->Execute(); // here when pass "ôpen" to lcQuery, it crash

如何正确地将“ôpen”添加到我的 URL？

Answer 1

HTTP 标头在请求Content-Type: application/x-www-form-urlencoded; charset=UTF-8中没有意义GET，仅在POST请求中。

Embarcadero 的 REST 框架不能正确处理非 ASCII 字符集。即使它在内部使用 Indy，它也没有使用 Indy 的字符集处理。因此，为了发送 UTF-8 编码的数据，您必须：

1. 手动将a 编码UnicodeString为 UTF-8，然后将 UTF-8 八位位组放回 aUnicodeString以便TRESTRequest可以发送它们：

   UnicodeString EncodeAsUtf8(const UnicodeString &s)
   {
       UTF8String utf8 = s;
       UnicodeString ret;
       ret.SetLength(utf8.Length());
       for (int x = 1; x <= utf8.Length(); ++x)
           ret[x] = (WideChar) utf8[x];
       return ret;
   }
   
   ...
   
   RESTRequest->ResetToDefaults();
   RESTRequest->Method = rmGET;
   RESTRequest->Resource = L"XXX/collection1" + Form1->teReuqestHandler->Text;
   RESTRequest->AddParameter(L"q", EncodeAsUtf8(Form1->teQuery->Text), TRESTRequestParameterKind::pkGETorPOST);
   String str1 = RESTRequest->GetFullRequestURL();
   RESTRequest->Execute();
   

2. 自己编码参数数据：

   #include <IdGlobal.hpp>
   #include <IdURI.hpp>
   
   RESTRequest->ResetToDefaults();
   RESTRequest->Method = rmGET;
   RESTRequest->Resource = L"XXX/collection1" + Form1->teReuqestHandler->Text;
   RESTRequest->AddParameter(L"q", TIdURI::ParamsEncode(Form1->teQuery->Text, IndyTextEncoding_UTF8), TRESTRequestParameterKind::pkGETorPOST, TRESTRequestParameterOptions() << TRESTRequestParameterOption::poDoNotEncode);
   String str1 = RESTRequest->GetFullRequestURL();
   RESTRequest->Execute();
   

   或者：

   #include <IdGlobal.hpp>
   #include <IdURI.hpp>
   
   RESTRequest->ResetToDefaults();
   RESTRequest->Method = rmGET;
   RESTRequest->Resource = L"XXX/collection1" + Form1->teReuqestHandler->Text + L"?q={q}";
   RESTRequest->AddParameter(L"q", TIdURI::ParamsEncode(Form1->teQuery->Text, IndyTextEncoding_UTF8), TRESTRequestParameterKind::pkURLSEGMENT, TRESTRequestParameterOptions() << TRESTRequestParameterOption::poDoNotEncode);
   String str1 = RESTRequest->GetFullRequestURL();
   RESTRequest->Execute();
   

否则，切换到 Indy 的TIdHTTP组件：

UnicodeString Response = IdHTTP1->Get(L"http://server/XXX/collection1" + Form1->teReuqestHandler->Text + L"?q=" + TIdURI::ParamsEncode(Form1->teQuery->Text, IndyTextEncoding_UTF8));