UE Http笔记

c++参考链接

UE4 开发如何使用 Http 请求_wx61ae2f5191643的技术博客_51CTO博客

虚幻引擎:UEC++如何对JSON文件进行读写?-CSDN博客

UE4 HTTP使用

官方免费插件

VaRest

在代码插件创建的VaRest - 虚幻引擎商城

UE5在蓝图中使用Varest插件Get，Post两种常见请求方式_慢慢沉的博客-CSDN博客

UE4使用VaRest插件请求httpAPI以及解析json格式数据_ue4 varest-CSDN博客

*请求以后接收Json一定要注意这里.不要用错对象了.我在这卡了10分钟才找到问题出在哪

示例代码

里面有部分是我测试Http下载文件的代码.所以实际效果很乱.自行理解删减

• 单纯的Http请求.返回值因为与下面这个下载是同一个Class里面所以是混乱的
• Http下载文件 UE Http下载文件/解压压缩包_Vince丶的博客-CSDN博客

xxx..Build.cs

"HTTP",
"Json",
"JsonUtilities"

.h

#pragma once

#include "CoreMinimal.h"
#include "Kismet/BlueprintAsyncActionBase.h"
#include "Interfaces/IHttpRequest.h"
#include "AsyncHttpObject.generated.h"

#pragma region One

DECLARE_DYNAMIC_MULTICAST_DELEGATE_ThreeParams(FDownloadProgressDelegate,
	const int32&, ReceivedDataInBytes,
	const int32&, TotalDataInBytes,
	const TArray&, BinaryData
);
DECLARE_DYNAMIC_MULTICAST_DELEGATE(FDownloadDelegate);

#pragma endregion

#pragma region Two

UENUM(BlueprintType)
enum class EPTRequestVerb : uint8
{
	GET,
	POST
};


#pragma endregion
/**
 *
 */
UCLASS()
class PIECETOGETHERTOOLS_API UAsyncHttpObject : public UBlueprintAsyncActionBase
{
	GENERATED_BODY()

public:

#pragma region One
	UFUNCTION(BlueprintCallable, Category = "Vince | AsyncHttp", meta = (BlueprintInternalUseOnly = "true"))
	static UAsyncHttpObject* AsyncHttpDownload(const FString& URL, FString fileSavePath, FString ileSaveName);

	void DownloadRequestStart(const FString& url);
	void DownloadRequestHandle(FHttpRequestPtr request, FHttpResponsePtr response, bool bWasSuccessful);
	void DownloadProgress(FHttpRequestPtr request, int32 bytesSent, int32 bytesReceived);

	//输出节点
	UPROPERTY(BlueprintAssignable, Category = "Vince | AsyncHttp")
	FDownloadProgressDelegate OnProgressUpdate; //最好把有参数的放在前面，不然参数在蓝图节点有时候被吃掉了

	//输出节点
	UPROPERTY(BlueprintAssignable, Category = "Vince | AsyncHttp")
	FDownloadDelegate OnSucc;

	//输出节点
	UPROPERTY(BlueprintAssignable, Category = "Vince | AsyncHttp")
	FDownloadDelegate OnFailed;



#pragma endregion

#pragma region Two

	UFUNCTION(BlueprintCallable, Category = "Vince | AsyncHttp", meta = (BlueprintInternalUseOnly = "true"))
	static UAsyncHttpObject* ConnectAsyncHttp(EPTRequestVerb verb, const FString& URL);

	FString MassageBody = TEXT("");

	void AsyncRequestHandle(FHttpRequestPtr request, FHttpResponsePtr response, bool bWasSuccessful);


#pragma endregion

.cpp

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


#include "AsyncHttpObject.h"
#include "HttpModule.h"
#include "Interfaces/IHttpResponse.h"
#include "Misc/Paths.h"
#include "HAL/PlatformFileManager.h"
#include "GenericPlatform/GenericPlatformFile.h"



#pragma region One

//存储目录
FString FileSavePath =TEXT("");

//存储名字
FString FileSaveName = TEXT("");

UAsyncHttpObject* UAsyncHttpObject::AsyncHttpDownload(const FString& URL, FString fileSavePath, FString fileSaveName)
{

	UAsyncHttpObject* AsyncHttpObject = NewObject();
	AsyncHttpObject->DownloadRequestStart(URL);

	FileSavePath = fileSavePath;
	FileSaveName = fileSaveName;

	return AsyncHttpObject;
}

//开始请求下载
void UAsyncHttpObject::DownloadRequestStart(const FString& url)
{
	TSharedRef request = FHttpModule::Get().CreateRequest();
	request->SetVerb("GET");
	request->SetURL(url);
	request->OnProcessRequestComplete().BindUObject(this, &UAsyncHttpObject::DownloadRequestHandle); //请求回调
	request->OnRequestProgress().BindUObject(this, &UAsyncHttpObject::DownloadProgress);// 下载进度
	request->ProcessRequest();



	RemoveFromRoot(); // 手动GC
}

请求回调
void UAsyncHttpObject::DownloadRequestHandle(FHttpRequestPtr request, FHttpResponsePtr response, bool bWasSuccessful)
{
	RemoveFromRoot();


	if (bWasSuccessful && response.IsValid() && EHttpResponseCodes::IsOk(response->GetResponseCode()))
	{
		if (response->GetContentLength() > 0) {
			TArray EmptyData;
			OnProgressUpdate.Broadcast(response->GetContentLength(), response->GetContentLength(), EmptyData);
		}

		//FString FileSavePath = FPaths::ProjectDir() + "/download/gameplay.png";

	     
		//下载返回类型设置
		FString sType, SLeft, SRight;
		sType = response->GetHeader(TEXT("Content-Type"));
		sType.Split("/",&SLeft,&SRight);
		FileSaveName.Append(FString::Printf(TEXT(".%s"), *SRight)) ;

		//组合 存储地址
		FileSavePath = FPaths::Combine(FileSavePath, FileSaveName);

		FString Path, Filename, Extension;
		FPaths::Split(FileSavePath, Path, Filename, Extension);


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

		if (!PlatformFile.DirectoryExists(*Path))
		{
			if (!PlatformFile.CreateDirectoryTree(*Path))
			{
				UE_LOG(LogTemp, Error, TEXT("Create Directory Failed!"));
				OnFailed.Broadcast();
				return;
			}
		}

		IFileHandle* FileHandle = PlatformFile.OpenWrite(*FileSavePath);
		if (FileHandle)
		{
			FileHandle->Write(response->GetContent().GetData(), response->GetContentLength());
			delete FileHandle;
			OnSucc.Broadcast();
			return;
		}
		else {
			UE_LOG(LogTemp, Error, TEXT("Save File Failed!"));
			OnFailed.Broadcast();
			return;
		}

	}
	UE_LOG(LogTemp, Error, TEXT("download File Failed!"));
	OnFailed.Broadcast();
	return;
}

// 下载进度
void UAsyncHttpObject::DownloadProgress(FHttpRequestPtr request, int32 bytesSent, int32 bytesReceived)
{
	if (request->GetResponse()->GetContentLength() > 0)
	{
		TArray EmptyData;
		OnProgressUpdate.Broadcast(bytesReceived, request->GetResponse()->GetContentLength(), EmptyData);
	}
}


UAsyncHttpObject* UAsyncHttpObject::ConnectAsyncHttp(EPTRequestVerb verb, const FString& URL)
{
	UAsyncHttpObject* AsyncHttpObject = NewObject();
	AsyncHttpObject->MassageBody = "";

	if (URL.IsEmpty())
	{
	//	AsyncHttpObject->OnFailed.Broadcast("URL Is Null");
	}


	TSharedRef request = FHttpModule::Get().CreateRequest();


	switch (verb)
	{
	case EPTRequestVerb::GET:

		//设置请求方式
		request->SetVerb(TEXT("GET"));
		//设置头
		request->SetHeader(TEXT("Content-Type"), TEXT("application/json;charset=utf-8"));

		break;
	case EPTRequestVerb::POST:


		request->SetVerb(TEXT("POST"));
		request->SetHeader(TEXT("Content-Type"), TEXT("application/x - www-form-urlencoded"));
		break;
	default:
		break;
	}

	//设置URL
	request->SetURL(URL);

	//绑定回调
	request->OnProcessRequestComplete().BindUObject(AsyncHttpObject, &UAsyncHttpObject::AsyncRequestHandle); //请求回调
	request->OnRequestProgress().BindUObject(AsyncHttpObject, &UAsyncHttpObject::DownloadProgress);// 下载进度

	内容
	TSharedRef pJsonObject = MakeShared();
	TSharedRef pJsonObject1 = MakeShared();

	//
	//pJsonObject->SetStringField("TD", URL);
	//pJsonObject->SetStringField("TD1", "123");
	//
	pJsonObject1->SetObjectField("TDB",pJsonObject);
	//FString OutputString;
	//TSharedRef> Writer = TJsonWriterFactory<>::Create(&OutputString);
	//FJsonSerializer::Serialize(pJsonObject1, Writer);

	Json内容设置
	//request->SetContentAsString(OutputString);

	//GEngine->AddOnScreenDebugMessage(-1, 10.0f, FColor::Yellow, OutputString, false);


	//请求
	request->ProcessRequest();

	AsyncHttpObject->RemoveFromRoot(); // 手动GC

	return AsyncHttpObject;

}

void UAsyncHttpObject::AsyncRequestHandle(FHttpRequestPtr request, FHttpResponsePtr response, bool bWasSuccessful)
{
	RemoveFromRoot(); // 手动GC

	if (bWasSuccessful && response.IsValid() && EHttpResponseCodes::IsOk(response->GetResponseCode()))
	{
	
		// 获得返回的json数据
		TSharedRef> JsonReader = TJsonReaderFactory::Create(response->GetContentAsString());
		// 把FString转成TCHAR
		TCHAR* serializedChar = response->GetContentAsString().GetCharArray().GetData();
		// 解决中文乱码问题，服务端也是utf-8
		TCHAR_TO_UTF8(serializedChar);
		FString myData(serializedChar);

		// 创建Json对象
		TSharedPtr JsonObject;
		// 反序列化json
		bool bIsOk = FJsonSerializer::Deserialize(JsonReader, JsonObject);
		// 判断是否反序列化成功

		if (bIsOk)
		{
			FString data = JsonObject->GetStringField("city");
			//FWHelper::Debug(data);
			UE_LOG(LogTemp, Warning, TEXT("%s"), *data);
			UE_LOG(LogTemp, Warning, TEXT("%s"), *myData);

			FString OutputString;
			TSharedRef>> Writer = TJsonWriterFactory>::Create(&OutputString);
			FJsonSerializer::Serialize(JsonObject.ToSharedRef(), Writer); //Serialize：把内存中的对象转为便于存储和传输的数据
			//打印
			UE_LOG(LogNet, Warning, TEXT("output 1:\n%s"), *OutputString);

			TSharedPtr Object = JsonObject->GetObjectField(TEXT("name"));
			TSharedPtr ObjectField = Object->GetObjectField(TEXT("realtime"));
			FString StringField = ObjectField->GetStringField("text");

		}


	}
}



#pragma endregion



//void UAsyncHttpObject::XieJson(FString& outjsonStr, const UObject* WorldContextObject)
//{
//	// 声明一个存储Json内容的字符串
//	FString JsonStr;
//	//GetJSONStr(JsonStr,WorldContextObject);
//
//	// 创建一个Json编写器
//	TSharedRef>> JsonWriter = TJsonWriterFactory>::Create(&JsonStr);
//	//TSharedRef> JsonWriter = TJsonWriterFactory<>::Create(&JsonStr);
//
//	// 声明Json对象写入开始
//	JsonWriter->WriteObjectStart();
//	JsonWriter->WriteValue(TEXT("Time"), TEXT("21"));
//
//	// 声明Json数组写入开始
//	JsonWriter->WriteArrayStart(TEXT("Data"));
//	for (int i = 0; i < 2; i++)
//	{
//		JsonWriter->WriteObjectStart();
//		JsonWriter->WriteValue(TEXT("key"), i);
//		JsonWriter->WriteObjectEnd();
//	}
//	JsonWriter->WriteArrayEnd();
//
//	JsonWriter->WriteObjectEnd();
//	// 停止写入
//	JsonWriter->Close();
//
//	UE_LOG(LogTemp, Warning, TEXT("%s"), *JsonStr);
//	outjsonStr = JsonStr;
//
//	GEngine->AddOnScreenDebugMessage(-1, 10.0f, FColor::Yellow, outjsonStr, false);
//}

写入Http请求内容示例

写入Http请求Json内容我自己测试的可以有2种习惯.看自己习惯.c++能力有限.可能描述有误.自行理解把.

第一种直接给 FJsonObject 直接写入 .最后在转成Fstring

内容
TSharedRef pJsonObject = MakeShared();
TSharedRef pJsonObject1 = MakeShared();


pJsonObject->SetStringField("TD", URL);
pJsonObject->SetStringField("TD1", "123");

//pJsonObject1->SetObjectField("TDB",pJsonObject);
FString OutputString;
TSharedRef> Writer = TJsonWriterFactory<>::Create(&OutputString);
FJsonSerializer::Serialize(pJsonObject1, Writer);

//Json内容设置
request->SetContentAsString(OutputString);

GEngine->AddOnScreenDebugMessage(-1, 10.0f, FColor::Yellow, OutputString, false);

第二种 创建一个Json编写器 直接编写Json.

.h

UFUNCTION(BlueprintCallable, Category = "Vince | AsyncHttp", meta = (WorldContext = "WorldContextObject"))
static	void XieJson(FString& outjsonStr, const UObject* WorldContextObject);

.cpp

void UPieceTogetherToolsBPLibrary::XieJson(FString& outjsonStr, const UObject* WorldContextObject)
{
	// 声明一个存储Json内容的字符串
	FString JsonStr;
	//GetJSONStr(JsonStr,WorldContextObject);

	// 创建一个Json编写器
	TSharedRef>> JsonWriter = TJsonWriterFactory>::Create(&JsonStr);
	//TSharedRef> JsonWriter = TJsonWriterFactory<>::Create(&JsonStr);

	// 声明Json对象写入开始
	JsonWriter->WriteObjectStart();
	JsonWriter->WriteValue(TEXT("Time"), TEXT("21"));

	// 声明Json数组写入开始
	JsonWriter->WriteArrayStart(TEXT("Data"));
	for (int i = 0; i < 2; i++)
	{
		JsonWriter->WriteValue(TEXT("key"), i);
	}
	JsonWriter->WriteArrayEnd();

	JsonWriter->WriteObjectEnd();
	// 停止写入
	JsonWriter->Close();

	UE_LOG(LogTemp, Warning, TEXT("%s"), *JsonStr);
	outjsonStr = JsonStr;

	GEngine->AddOnScreenDebugMessage(-1, 10.0f, FColor::Yellow, outjsonStr, false);
}

Http接收回调解析数据示例

.cpp

		// 获得返回的json数据
		TSharedRef> JsonReader = TJsonReaderFactory::Create(response->GetContentAsString());
		// 把FString转成TCHAR
		TCHAR* serializedChar = response->GetContentAsString().GetCharArray().GetData();
		// 解决中文乱码问题，服务端也是utf-8
		TCHAR_TO_UTF8(serializedChar);
		FString myData(serializedChar);

		// 创建Json对象
		TSharedPtr JsonObject;
		// 反序列化json
		bool bIsOk = FJsonSerializer::Deserialize(JsonReader, JsonObject);
		// 判断是否反序列化成功

		if (bIsOk)
		{
			FString data = JsonObject->GetStringField("city");
			//FWHelper::Debug(data);
			UE_LOG(LogTemp, Warning, TEXT("%s"), *data);
			UE_LOG(LogTemp, Warning, TEXT("%s"), *myData);

			FString OutputString;
			TSharedRef>> Writer = TJsonWriterFactory>::Create(&OutputString);
			FJsonSerializer::Serialize(JsonObject.ToSharedRef(), Writer); //Serialize：把内存中的对象转为便于存储和传输的数据
			//打印
			UE_LOG(LogNet, Warning, TEXT("output 1:\n%s"), *OutputString);

			TSharedPtr Object = JsonObject->GetObjectField(TEXT("name"));
			TSharedPtr ObjectField = Object->GetObjectField(TEXT("realtime"));
			FString StringField = ObjectField->GetStringField("text");

		}