【UE4学习】22_C++输出字符串及FString字符串转换

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C++输出字符串

输出字符串到output log中

FString filePathUE_LOG(LogTemp, Log, TEXT("%s"), *filePath);UE_LOG(LogTemp, Error, TEXT("Hello,World!"));

输出字符串到屏幕上

FString filePath;GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Green, FString::Printf(TEXT("DLL_Init")));GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Green, FString::Printf(TEXT("%s"), *filePath));

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字符串转换

Converting FString to FNames

FString TheString = "UE4_C++_IS_Awesome";FName ConvertedFString = FName(*TheString);

Converting std::string to FString

#include <string>//....std::string TestString = "Happy"; FString HappyString(TestString.c_str());

Converting FString to std::string

#include <string>//....FString UE4Str = "Flowers";std::string MyStdString(TCHAR_TO_UTF8(*UE4Str));

• 数值转std::to_string
  
  • std::string to_string( long value );
  • std::string to_string( long long value );
  • std::string to_string( unsigned value );
  • std::string to_string( unsigned long value );
  • std::string to_string( unsigned long long value );
  • std::string to_string( float value );
  • std::string to_string( double value );
  • std::string to_string( long double value );

Converting FString to Integer

FString TheString = "123.021";int32 MyShinyNewInt = FCString::Atoi(*TheString);

Converting FString to Float

FString TheString = "123.021";int32 MyShinyNewInt = FCString::Atof(*TheString);

Converting Float/Integer to FString

FString NewString = FString::FromInt(YourInt);FString VeryCleanString = FString::SanitizeFloat(YourFloat);

UE4 Source Header References

CString.hUnrealString.hNameTypes.hStringConv.h (TCHAR_TO_ANSI etc)

CString.h可以查到更多，如

atoi64 (string to int64)Atod    (string to double precision float)

更多关于FString的操作可以到UnrealString.h找到.

Converting FArrayReaderPtr to FString

uint8 data[512];  FMemory::Memzero(data, 512);  FMemory::Memcpy(data, ArrayReaderPtr->GetData(), ArrayReaderPtr->Num());  FString str = ((const char*)data);  

Converting Array to FString

TArray<uint8> content;  ...  const std::string cstr(reinterpret_cast<const char*>(content.GetData()), content.Num());  FString frameAsFString = cstr.c_str();  UE_LOG(VRSLog, Warning, TEXT("%s"), *frameAsFString);  

Converting FString to Array

FString JsonStr;  TArray<uint8> content;  content.SetNum(JsonStr.Len());  memcpy(content.GetData(), TCHAR_TO_ANSI(*JsonStr), JsonStr.Len());   

FString StrData;  const TCHAR* StrPtr = *StrData;  FTCHARToUTF8 UTF8String(StrPtr);  int32 CTXSize = UTF8String.Length();  TArray<uint8> URLData;  URLData.SetNum(CTXSize);  memcpy(URLData.GetData(), UTF8String.Get(), CTXSize);  

Converting FString to char *

///1FString strstring t = TCHAR_TO_UTF8(*str);char * returnvalue = (char *)malloc(sizeof(char) * (t.length() + 1));strncpy_s(returnvalue, t.length() , t.c_str(), t.length());  ///2int ARPG_Database::BP_GetColumnIndex(int resultSet, FString columnName){    return GetColumnIndex(resultSet, TCHAR_TO_ANSI(*columnName));}int ARPG_Database::GetColumnIndex(int iResult, const char* columnName){}

Converting FString to const char *

const char *plainText= TCHAR_TO_ANSI(*aes_content);

Converting FString to TCHAR *

 int ARPG_Database::BP_GetColumnIndex(int resultSet, FString columnName) {     return GetColumnIndex(resultSet, *columnName); } int ARPG_Database::GetColumnIndex(int iResult, const TCHAR* columnName) { }

Converting FString to FText

FString Str = TEXT("str");  FText Text = FText::FromString(Str);

Converting FText to FString

FString Name = NameDesc->GetText().ToString();  

参考

• Logs, Printing Messages To Yourself During Runtime

• UEngine::AddOnScreenDebugMessage

• String Conversions: FString to FName, FString to Int32, Float to FString

• 字符编码

• String Casting Fun in Unreal Engine 4 UPDATED

• 虚幻4学习—UE4中的字符串转换