简概:
本次文章主要介绍给视频添加动效水印的几种方式,以及实现代码。
使用AVFoundation + CoreAnimation 合成方式
基于Lottie 核心也是 CoreAnimation ,这里我们也可以使用AVFoundation + Lottie 合成方式
我们同样可以使用序列帧资源或者gif资源 来编写一段keyFrameAnination,这里我们就介绍一段 AVFoundation + Gif 合成方式
使用 GPUImageUIElement 将序列帧资源合并在目标资源上
使用 GPUImage 将水印视频合并在目标资源上
如果你有问题,或者对下述文字有任何意见与建议,除了在文章最后留言,还可以在微博阳眼的熊1993上给我留言,或者联系我的邮箱hu-yangyang@qq.com,以及访问我的Github。
文章某尾会给到Demo。
视频处理后效果 GIF
原视频.gif
CoreAnimation.gif
Lottie.gif
GIF.gif
GPUImageType1.gif
GPUImageType2.gif
1.使用AVFoundation + CoreAnimation 合成方式
#pragma mark CorAnimation+ (void)addWaterMarkTypeWithCorAnimationAndInputVideoURL:(NSURL*)InputURL WithCompletionHandler:(void (^)(NSURL* outPutURL, int code))handler{ NSDictionary *opts = [NSDictionary dictionaryWithObject:@(YES) forKey:AVURLAssetPreferPreciseDurationAndTimingKey]; AVAsset *videoAsset = [AVURLAsset URLAssetWithURL:InputURL options:opts]; AVMutableComposition *mixComposition = [[AVMutableComposition alloc] init]; AVMutableCompositionTrack *videoTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid]; NSError *errorVideo = [NSError new]; AVAssetTrack *assetVideoTrack = [[videoAsset tracksWithMediaType:AVMediaTypeVideo]firstObject]; CMTime endTime = assetVideoTrack.asset.duration; BOOL bl = [videoTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, assetVideoTrack.asset.duration) ofTrack:assetVideoTrack atTime:kCMTimeZero error:&errorVideo]; videoTrack.preferredTransform = assetVideoTrack.preferredTransform; NSLog(@"errorVideo:%ld%d",errorVideo.code,bl); NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDirectory = [paths objectAtIndex:0]; NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; formatter.dateFormat = @"yyyyMMddHHmmss"; NSString *outPutFileName = [formatter stringFromDate:[NSDate dateWithTimeIntervalSinceNow:0]]; NSString *myPathDocs = [documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:@"%@.mov",outPutFileName]]; NSURL* outPutVideoUrl = [NSURL fileURLWithPath:myPathDocs]; CGSize videoSize = [videoTrack naturalSize]; UIFont *font = [UIFont systemFontOfSize:60.0]; CATextLayer *aLayer = [[CATextLayer alloc] init]; [aLayer setFontSize:60]; [aLayer setString:@"H"]; [aLayer setAlignmentMode:kCAAlignmentCenter]; [aLayer setForegroundColor:[[UIColor greenColor] CGColor]]; [aLayer setBackgroundColor:[UIColor clearColor].CGColor]; CGSize textSize = [@"H" sizeWithAttributes:[NSDictionary dictionaryWithObjectsAndKeys:font,NSFontAttributeName, nil]]; [aLayer setFrame:CGRectMake(240, 470, textSize.width, textSize.height)]; aLayer.anchorPoint = CGPointMake(0.5, 1.0); CATextLayer *bLayer = [[CATextLayer alloc] init]; [bLayer setFontSize:60]; [bLayer setString:@"E"]; [bLayer setAlignmentMode:kCAAlignmentCenter]; [bLayer setForegroundColor:[[UIColor greenColor] CGColor]]; [bLayer setBackgroundColor:[UIColor clearColor].CGColor]; CGSize textSizeb = [@"E" sizeWithAttributes:[NSDictionary dictionaryWithObjectsAndKeys:font,NSFontAttributeName, nil]]; [bLayer setFrame:CGRectMake(240 + textSize.width, 470 , textSizeb.width, textSizeb.height)]; bLayer.anchorPoint = CGPointMake(0.5, 1.0); CATextLayer *cLayer = [[CATextLayer alloc] init]; [cLayer setFontSize:60]; [cLayer setString:@"L"]; [cLayer setAlignmentMode:kCAAlignmentCenter]; [cLayer setForegroundColor:[[UIColor greenColor] CGColor]]; [cLayer setBackgroundColor:[UIColor clearColor].CGColor]; CGSize textSizec = [@"L" sizeWithAttributes:[NSDictionary dictionaryWithObjectsAndKeys:font,NSFontAttributeName, nil]]; [cLayer setFrame:CGRectMake(240 + textSizeb.width + textSize.width, 470 , textSizec.width, textSizec.height)]; cLayer.anchorPoint = CGPointMake(0.5, 1.0); CATextLayer *dLayer = [[CATextLayer alloc] init]; [dLayer setFontSize:60]; [dLayer setString:@"L"]; [dLayer setAlignmentMode:kCAAlignmentCenter]; [dLayer setForegroundColor:[[UIColor greenColor] CGColor]]; [dLayer setBackgroundColor:[UIColor clearColor].CGColor]; CGSize textSized = [@"L" sizeWithAttributes:[NSDictionary dictionaryWithObjectsAndKeys:font,NSFontAttributeName, nil]]; [dLayer setFrame:CGRectMake(240 + textSizec.width+ textSizeb.width + textSize.width, 470 , textSized.width, textSized.height)]; dLayer.anchorPoint = CGPointMake(0.5, 1.0); CATextLayer *eLayer = [[CATextLayer alloc] init]; [eLayer setFontSize:60]; [eLayer setString:@"O"]; [eLayer setAlignmentMode:kCAAlignmentCenter]; [eLayer setForegroundColor:[[UIColor greenColor] CGColor]]; [eLayer setBackgroundColor:[UIColor clearColor].CGColor]; CGSize textSizede = [@"O" sizeWithAttributes:[NSDictionary dictionaryWithObjectsAndKeys:font,NSFontAttributeName, nil]]; [eLayer setFrame:CGRectMake(240 + textSized.width + textSizec.width+ textSizeb.width + textSize.width, 470 , textSizede.width, textSizede.height)]; eLayer.anchorPoint = CGPointMake(0.5, 1.0); CABasicAnimation* basicAni = [CABasicAnimation animationWithKeyPath:@"transform.scale"]; basicAni.fromValue = @(0.2f); basicAni.toValue = @(1.0f); basicAni.beginTime = AVCoreAnimationBeginTimeAtZero; basicAni.duration = 2.0f; basicAni.repeatCount = HUGE_VALF; basicAni.removedOnCompletion = NO; basicAni.fillMode = kCAFillModeForwards; [aLayer addAnimation:basicAni forKey:nil]; [bLayer addAnimation:basicAni forKey:nil]; [cLayer addAnimation:basicAni forKey:nil]; [dLayer addAnimation:basicAni forKey:nil]; [eLayer addAnimation:basicAni forKey:nil]; CALayer *parentLayer = [CALayer layer]; CALayer *videoLayer = [CALayer layer]; parentLayer.frame = CGRectMake(0, 0, videoSize.width, videoSize.height); videoLayer.frame = CGRectMake(0, 0, videoSize.width, videoSize.height); [parentLayer addSublayer:videoLayer]; [parentLayer addSublayer:aLayer]; [parentLayer addSublayer:bLayer]; [parentLayer addSublayer:cLayer]; [parentLayer addSublayer:dLayer]; [parentLayer addSublayer:eLayer]; AVMutableVideoComposition* videoComp = [AVMutableVideoComposition videoComposition]; videoComp.renderSize = videoSize; parentLayer.geometryFlipped = true; videoComp.frameDuration = CMTimeMake(1, 30); videoComp.animationTool = [AVVideoCompositionCoreAnimationTool videoCompositionCoreAnimationToolWithPostProcessingAsVideoLayer:videoLayer inLayer:parentLayer]; AVMutableVideoCompositionInstruction* instruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction]; instruction.timeRange = CMTimeRangeMake(kCMTimeZero, endTime); AVMutableVideoCompositionLayerInstruction* layerInstruction = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:videoTrack]; instruction.layerInstructions = [NSArray arrayWithObjects:layerInstruction, nil]; videoComp.instructions = [NSArray arrayWithObject: instruction]; AVAssetExportSession* exporter = [[AVAssetExportSession alloc] initWithAsset:mixComposition presetName:AVAssetExportPresetHighestQuality]; exporter.outputURL=outPutVideoUrl; exporter.outputFileType = AVFileTypeMPEG4; exporter.shouldOptimizeForNetworkUse = YES; exporter.videoComposition = videoComp; [exporter exportAsynchronouslyWithCompletionHandler:^{ dispatch_async(dispatch_get_main_queue(), ^{ //这里是输出视频之后的操作,做你想做的 NSLog(@"输出视频地址:%@ andCode:%@",myPathDocs,exporter.error); handler(outPutVideoUrl,(int)exporter.error.code); }); }]; }
2.基于Lottie 核心也是 CoreAnimation ,这里我们也可以使用AVFoundation + Lottie 合成方式
与第一段代码不同的地方
LOTAnimationView* animation = [LOTAnimationView animationNamed:@"青蛙"]; animation.frame = CGRectMake(150 , 340 , 240 , 240 ); animation.animationSpeed = 5.0 ; animation.loopAnimation = YES; [animation play]; CALayer *parentLayer = [CALayer layer]; CALayer *videoLayer = [CALayer layer]; parentLayer.frame = CGRectMake(0, 0, videoSize.width, videoSize.height); videoLayer.frame = CGRectMake(0, 0, videoSize.width, videoSize.height); [parentLayer addSublayer:videoLayer]; [parentLayer addSublayer:animation.layer];
3.我们同样可以使用序列帧资源或者gif资源 来编写一段keyFrameAnination,这里我们就介绍一段 AVFoundation + Gif 合成方式
与第一段代码不同的地方是将gif 转成layer 的KEYFrameAnimation
CALayer *gifLayer1 = [[CALayer alloc] init]; gifLayer1.frame = CGRectMake(150 , 340 , 298 , 253 ); CAKeyframeAnimation *gifLayer1Animation = [WatermarkEngine animationForGifWithURL:[[NSBundle mainBundle] URLForResource:@"雪人完成_1" withExtension:@"gif"]]; gifLayer1Animation.beginTime = AVCoreAnimationBeginTimeAtZero; gifLayer1Animation.removedOnCompletion = NO; [gifLayer1 addAnimation:gifLayer1Animation forKey:@"gif"]; CALayer *parentLayer = [CALayer layer]; CALayer *videoLayer = [CALayer layer]; parentLayer.frame = CGRectMake(0, 0, videoSize.width, videoSize.height); videoLayer.frame = CGRectMake(0, 0, videoSize.width, videoSize.height); [parentLayer addSublayer:videoLayer]; [parentLayer addSublayer:gifLayer1];
+ (CAKeyframeAnimation *)animationForGifWithURL:(NSURL *)url { CAKeyframeAnimation *animation = [CAKeyframeAnimation animationWithKeyPath:@"contents"]; NSMutableArray * frames = [NSMutableArray new]; NSMutableArray *delayTimes = [NSMutableArray new]; CGFloat totalTime = 0.0; CGFloat gifWidth; CGFloat gifHeight; CGImageSourceRef gifSource = CGImageSourceCreateWithURL((CFURLRef)url, NULL); // get frame count size_t frameCount = CGImageSourceGetCount(gifSource); for (size_t i = 0; i < frameCount; ++i) { // get each frame CGImageRef frame = CGImageSourceCreateImageAtIndex(gifSource, i, NULL); [frames addObject:(__bridge id)frame]; CGImageRelease(frame); // get gif info with each frame NSDictionary *dict = (NSDictionary*)CFBridgingRelease(CGImageSourceCopyPropertiesAtIndex(gifSource, i, NULL)); NSLog(@"kCGImagePropertyGIFDictionary %@", [dict valueForKey:(NSString*)kCGImagePropertyGIFDictionary]); // get gif size gifWidth = [[dict valueForKey:(NSString*)kCGImagePropertyPixelWidth] floatValue]; gifHeight = [[dict valueForKey:(NSString*)kCGImagePropertyPixelHeight] floatValue]; // kCGImagePropertyGIFDictionary中kCGImagePropertyGIFDelayTime,kCGImagePropertyGIFUnclampedDelayTime值是一样的 NSDictionary *gifDict = [dict valueForKey:(NSString*)kCGImagePropertyGIFDictionary]; [delayTimes addObject:[gifDict valueForKey:(NSString*)kCGImagePropertyGIFUnclampedDelayTime]]; totalTime = totalTime + [[gifDict valueForKey:(NSString*)kCGImagePropertyGIFUnclampedDelayTime] floatValue]; // CFRelease((__bridge CFTypeRef)(dict)); // CFRelease((__bridge CFTypeRef)(dict)); } if (gifSource) { CFRelease(gifSource); } NSMutableArray *times = [NSMutableArray arrayWithCapacity:3]; CGFloat currentTime = 0; NSInteger count = delayTimes.count; for (int i = 0; i < count; ++i) { [times addObject:[NSNumber numberWithFloat:(currentTime / totalTime)]]; currentTime += [[delayTimes objectAtIndex:i] floatValue]; } NSMutableArray *images = [NSMutableArray arrayWithCapacity:3]; for (int i = 0; i < count; ++i) { [images addObject:[frames objectAtIndex:i]]; } animation.keyTimes = times; animation.values = images; animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear]; animation.duration = totalTime; animation.repeatCount = HUGE_VALF; return animation; }
4.使用 GPUImage 将水印视频合并在目标资源上
#pragma mark GPUImage TWO VIDEO INPUT+ (void)addWaterMarkTypeWithGPUImageAndInputVideoURL:(NSURL*)InputURL AndWaterMarkVideoURL:(NSURL*)InputURL2 WithCompletionHandler:(void (^)(NSURL* outPutURL, int code))handler{ NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDirectory = [paths objectAtIndex:0]; NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; formatter.dateFormat = @"yyyyMMddHHmmss"; NSString *outPutFileName = [formatter stringFromDate:[NSDate dateWithTimeIntervalSinceNow:0]]; NSString *myPathDocs = [documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:@"%@.mov",outPutFileName]]; NSURL* outPutVideoUrl = [NSURL fileURLWithPath:myPathDocs]; GPUImageMovie* movieFile = [[GPUImageMovie alloc] initWithURL:InputURL]; GPUImageMovie* movieFile2 = [[GPUImageMovie alloc] initWithURL:InputURL2]; GPUImageScreenBlendFilter* filter = [[GPUImageScreenBlendFilter alloc] init]; [movieFile addTarget:filter]; [movieFile2 addTarget:filter]; GPUImageMovieWriter* movieWriter = [[GPUImageMovieWriter alloc] initWithMovieURL:outPutVideoUrl size:CGSizeMake(540, 960) fileType:AVFileTypeQuickTimeMovie outputSettings: @ { AVVideoCodecKey: AVVideoCodecH264, AVVideoWidthKey: @540, //Set your resolution width here AVVideoHeightKey: @960, //set your resolution height here AVVideoCompressionPropertiesKey: @ { //2000*1000 建议800*1000-5000*1000 //AVVideoAverageBitRateKey: @2500000, // Give your bitrate here for lower size give low values AVVideoAverageBitRateKey: @5000000, AVVideoProfileLevelKey: AVVideoProfileLevelH264HighAutoLevel, AVVideoAverageNonDroppableFrameRateKey: @30, }, } ]; [filter addTarget:movieWriter]; AVAsset* videoAsset = [AVAsset assetWithURL:InputURL]; AVAssetTrack *assetVideoTrack = [[videoAsset tracksWithMediaType:AVMediaTypeVideo]firstObject]; movieWriter.transform = assetVideoTrack.preferredTransform; // [movie enableSynchronizedEncodingUsingMovieWriter:movieWriter]; [movieWriter startRecording]; [movieFile startProcessing]; [movieFile2 startProcessing]; [movieWriter setCompletionBlock:^{ dispatch_async(dispatch_get_main_queue(), ^{ NSLog(@"movieWriter Completion"); handler(outPutVideoUrl,1); }); }]; }
5.使用 GPUImageUIElement 将序列帧资源合并在目标资源上
#pragma mark GPUImageUIElement+ (void)addWaterMarkTypeWithGPUImageUIElementAndInputVideoURL:(NSURL*)InputURL WithCompletionHandler:(void (^)(NSURL* outPutURL, int code))handler{ NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDirectory = [paths objectAtIndex:0]; NSDateFormatter *formatter = [[NSDateFormatter alloc] init]; formatter.dateFormat = @"yyyyMMddHHmmss"; NSString *outPutFileName = [formatter stringFromDate:[NSDate dateWithTimeIntervalSinceNow:0]]; NSString *myPathDocs = [documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:@"%@.mov",outPutFileName]]; NSURL* outPutVideoUrl = [NSURL fileURLWithPath:myPathDocs]; GPUImageMovie* movieFile = [[GPUImageMovie alloc] initWithURL:InputURL]; NSValue *value = [NSValue valueWithCGRect:CGRectMake([UIScreen mainScreen].bounds.size.width/2.0 - (332 /2.0) , [UIScreen mainScreen].bounds.size.height/2.0 - (297 /2.0) , 332 , 297 )]; NSValue *value2 = [NSValue valueWithCGAffineTransform:CGAffineTransformMake(1, 0, 0, 1, 0, 0)]; UIView* view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 1, 1)]; GPUImageFilterGroup* filter = [WatermarkEngine addWatermarkWithResourcesNames:@[@"雨天青蛙"] Andframes:@[value] AndTransform:@[value2] AndLabelViews:@[view]]; [movieFile addTarget:filter]; GPUImageMovieWriter* movieWriter = [[GPUImageMovieWriter alloc] initWithMovieURL:outPutVideoUrl size:CGSizeMake(540, 960) fileType:AVFileTypeQuickTimeMovie outputSettings: @ { AVVideoCodecKey: AVVideoCodecH264, AVVideoWidthKey: @540, //Set your resolution width here AVVideoHeightKey: @960, //set your resolution height here AVVideoCompressionPropertiesKey: @ { //2000*1000 建议800*1000-5000*1000 //AVVideoAverageBitRateKey: @2500000, // Give your bitrate here for lower size give low values AVVideoAverageBitRateKey: @5000000, AVVideoProfileLevelKey: AVVideoProfileLevelH264HighAutoLevel, AVVideoAverageNonDroppableFrameRateKey: @30, }, } ]; [filter addTarget:movieWriter]; AVAsset* videoAsset = [AVAsset assetWithURL:InputURL]; AVAssetTrack *assetVideoTrack = [[videoAsset tracksWithMediaType:AVMediaTypeVideo]firstObject]; movieWriter.transform = assetVideoTrack.preferredTransform; // [movie enableSynchronizedEncodingUsingMovieWriter:movieWriter]; [movieWriter startRecording]; [movieFile startProcessing]; [movieWriter setCompletionBlock:^{ dispatch_async(dispatch_get_main_queue(), ^{ NSLog(@"movieWriter Completion"); handler(outPutVideoUrl,1); }); }]; }
+ (GPUImageFilterGroup*) addWatermarkWithResourcesNames:(NSArray* )resourcesNames Andframes:(NSArray*)frams AndTransform:(NSArray*)transforms AndLabelViews:(NSArray*)labelViews{ __block int currentPicIndex = 0; CGFloat width = CGRectGetWidth([UIScreen mainScreen].bounds); UIView* temp = [[UIView alloc] initWithFrame:[UIScreen mainScreen].bounds]; [temp setContentScaleFactor:[[UIScreen mainScreen] scale]]; __block UIImageView* waterImageView1 = [[UIImageView alloc] init]; __block UIImageView* waterImageView2 = [[UIImageView alloc] init]; __block UIImageView* waterImageView3 = [[UIImageView alloc] init]; for (int index = 0 ; index < resourcesNames.count ; index++) { if (index == 0) { waterImageView1.frame = [frams[index] CGRectValue]; UIImage* tempImage = [UIImage imageWithContentsOfFile: [[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:@"%@_d",resourcesNames[index],currentPicIndex] ofType:@"png"]]; waterImageView1.image = tempImage; waterImageView1.transform = [transforms[index] CGAffineTransformValue]; [temp addSubview:waterImageView1]; [temp addSubview:labelViews[index]]; }else if (index == 1){ waterImageView2.frame = [frams[index] CGRectValue]; UIImage* tempImage = [UIImage imageWithContentsOfFile: [[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:@"%@_d",resourcesNames[index],currentPicIndex] ofType:@"png"]]; waterImageView2.image = tempImage; waterImageView2.transform = [transforms[index] CGAffineTransformValue]; [temp addSubview:waterImageView2]; [temp addSubview:labelViews[index]]; }else{ waterImageView3.frame = [frams[index] CGRectValue]; UIImage* tempImage = [UIImage imageWithContentsOfFile: [[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:@"%@_d",resourcesNames[index],currentPicIndex] ofType:@"png"]]; waterImageView3.image = tempImage; waterImageView3.transform = [transforms[index] CGAffineTransformValue]; [temp addSubview:waterImageView3]; [temp addSubview:labelViews[index]]; } } GPUImageFilterGroup* filterGroup = [[GPUImageFilterGroup alloc] init]; GPUImageUIElement *uiElement = [[GPUImageUIElement alloc] initWithView:temp]; GPUImageTwoInputFilter* blendFilter = [[GPUImageTwoInputFilter alloc] initWithFragmentShaderFromString:[WatermarkEngine loadShader:@"AlphaBlend_Normal" extension:@"frag"]]; GPUImageFilter* filter = [[GPUImageFilter alloc] init]; GPUImageFilter* uiFilter = [[GPUImageFilter alloc] init]; [uiElement addTarget:uiFilter];// [uiFilter setInputRotation:kGPUImageRotateLeft atIndex:0]; [filter addTarget:blendFilter]; [uiFilter addTarget:blendFilter]; [filterGroup addFilter:filter]; [filterGroup addFilter:uiFilter]; [filterGroup addFilter:blendFilter]; [filterGroup setInitialFilters:@[filter]]; [filterGroup setTerminalFilter:blendFilter]; // 71 // __unsafe_unretained typeof(self) this = self; [filter setFrameProcessingCompletionBlock:^(GPUImageOutput * filter, CMTime frameTime) { currentPicIndex += 1; for (int index = 0 ; index < resourcesNames.count ; index++) { if (index == 0) { waterImageView1.image = [UIImage imageWithContentsOfFile: [[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:@"%@_d",resourcesNames[index],currentPicIndex] ofType:@"png"]]; }else if (index == 1){ waterImageView2.image = [UIImage imageWithContentsOfFile: [[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:@"%@_d",resourcesNames[index],currentPicIndex] ofType:@"png"]]; }else{ waterImageView3.image = [UIImage imageWithContentsOfFile: [[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:@"%@_d",resourcesNames[index],currentPicIndex] ofType:@"png"]]; } } if (currentPicIndex == 89) { currentPicIndex = 0; } [uiElement update]; }]; return filterGroup; }
+ (NSString * _Nonnull)loadShader:(NSString *)name extension:(NSString *)extenstion { NSURL *url = [[NSBundle mainBundle] URLForResource:name withExtension:extenstion]; return [NSString stringWithContentsOfURL:url encoding:NSUTF8StringEncoding error:nil]; }
作者:阳眼的熊
链接:https://www.jianshu.com/p/9f4f37e5abc6