iOS WKWebView识别H5中的图片资源

想获取H5的图片坐标那就需要JS注入了

- (void)handleSingleTap:(UITapGestureRecognizer *)recognizer {

CGPoint touchPoint = [recognizer locationInView:self.webView];

NSString *jsString = [NSString stringWithFormat:@"function getURLandRect(){\

var ele=document.elementFromPoint(%f, %f);\

var url=ele.src;\

var left=ele.getBoundingClientRect().left;\

var top=ele.getBoundingClientRect().top;\

var width=ele.getBoundingClientRect().width;\

var height=ele.getBoundingClientRect().height;\

var jsonString= `{\"url\":\"${url}\",\"left\":\"${left}\",\"top\":\"${top}\",\"width\":\"${width}\",\"height\":\"${height}\"}`;\

return(jsonString)} getURLandRect()", touchPoint.x, touchPoint.y];

[self.webView evaluateJavaScript:jsString completionHandler:^(id _Nullable result, NSError * _Nullable error) {

NSDictionary *resultDic = [SmallTools convertToDictionary:(NSString *)result];

NSString *imageURL = [SmallTools isNullToString:resultDic[@"url"]];

if (imageURL.length == 0 || [imageURL isEqualToString:@"undefined"]) {

return;

}

CGFloat imgX = [resultDic[@"left"] floatValue];

CGFloat imgY = [resultDic[@"top"] floatValue] + NAV_HEIGHT + 5;

CGFloat imgW = [resultDic[@"width"] floatValue];

CGFloat imgH = [resultDic[@"height"] floatValue];

self.photoView = [[YHPhotoBrowser alloc]init];

self.photoView.sourceView = self.view; //图片所在的父容器

self.photoView.urlImgArr = @[imageURL]; //网络链接图片的数组

if (imgX && imgY && imgW && imgH) { //原图片所在屏幕位置

self.photoView.sourceRect = CGRectMake(imgX, imgY, imgW, imgH);

}

self.photoView.indexTag = 0; //初始化进去显示的图片下标

[self.view addSubview:self.photoView]; //叠加在当前VC上

}];

}

这个JS方法document.elementFromPoint(%f, %f)根据传入的点返回该点最上层的对象，通过src找到图片的链接，然后getBoundingClientRect()方法能返回对象的八个属性left, top, right, bottom, x, y, width, height，根据需要获取相应属性构造原图的CGRect即可

这里附带一下判断NSString合法性以及JSON字符串转NSDictionary的工具方法+ (NSString *)isNullToString:(id)string { if ([string isEqual:@"NULL"] || [string isKindOfClass:[NSNull class]] || [string isEqual:[NSNull null]] || [string isEqual:NULL] || [[string class] isSubclassOfClass:[NSNull class]] || string == nil || string == NULL || [string isKindOfClass:[NSNull class]] || [[string stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]] length]==0 || [string isEqualToString:@""] || [string isEqualToString:@"(null)"]) { return @""; } else { return (NSString *)string; }}

+ (NSDictionary *)convertToDictionary:(NSString *)jsonStr {

NSData *data = [jsonStr dataUsingEncoding:NSUTF8StringEncoding];

NSDictionary *tempDic = [NSJSONSerialization JSONObjectWithData:data options:0 error:nil];

return tempDic;

}