虚幻引擎：4.22

VS：2017

将自定义的Log日志，存放到项目工程或者打包程序的Saved/Logs目录下

1、创建一个C++空类，我命名为GunTestLog

2、GunTestLog.h文件

// Fill out your copyright notice in the Description page of Project Settings.

#pragma once

#include "CoreMinimal.h"

void UE_GUNTEST_LOG_S(FString FileName, FString Value);

static FORCEINLINE void UE_GUNTEST_LOG(FString FileName, const TCHAR* Format, ...)

{

TCHAR TempStr[1024];

va_list Ptr;

va_start(Ptr, Format);

FCString::GetVarArgs(TempStr, ARRAY_COUNT(TempStr), ARRAY_COUNT(TempStr) - 1, Format, Ptr);

va_end(Ptr);

UE_GUNTEST_LOG_S(FileName, FString(TempStr));

}

3、GunTestLog.cpp文件

// Fill out your copyright notice in the Description page of Project Settings.

#include "GunTestLog.h"

#include "Paths.h"

#include "FileHelper.h"

#include "PlatformFileManager.h"

void UE_GUNTEST_LOG_S(FString _FileName, FString _Value)

{

static bool mIsNewLog = true;

FString mSaveDirectory = FPaths::ProjectSavedDir();

mSaveDirectory.Append("Logs/GunTest/");

FString mTmpFileName = _FileName;

mTmpFileName.Append(".log.txt");

IPlatformFile& mPlatformFile = FPlatformFileManager::Get().GetPlatformFile();

if (mPlatformFile.DirectoryExists(*mSaveDirectory))

{

mPlatformFile.CreateDirectoryTree(*mSaveDirectory);

}

//获取Log日志的绝对路径.

FString mAbsoluteFilePath = mSaveDirectory + "/" + mTmpFileName;

IFileManager* mFileManager = &IFileManager::Get();

uint32 WriteFlags = (uint32)(EFileWrite::FILEWRITE_Append);

//如果Log文件存在，修改名字另存.

if (mPlatformFile.FileExists(*mAbsoluteFilePath) && mIsNewLog)

{

mIsNewLog = false;

FString AbsoluteDestinationPath = mSaveDirectory + "/" + FDateTime::Now().ToString() + "-" + mTmpFileName;

mPlatformFile.MoveFile(*AbsoluteDestinationPath, *mAbsoluteFilePath);

mPlatformFile.DeleteFile(*mAbsoluteFilePath);

}

else

{

FString TextToSave = FDateTime::Now().ToString();

TextToSave.Append("-");

TextToSave.Append(_Value);

TextToSave.Append("\r\n");

FFileHelper::SaveStringToFile(TextToSave, *mAbsoluteFilePath, FFileHelper::EEncodingOptions::AutoDetect, mFileManager, WriteFlags);

}

}

4、在需要保存日志的.cpp文件中调用

5、第4步我是为了测试按键信息，然后将按键日志保存到Saved/Logs/GunTest/文件目录下