$(‘.content .saveCode‘).on(‘touchstart‘, function () {//touchstart        if (temp == 0) {            jump();        }        if (temp == 1) { android.savePic(image.src); }            });    function jump() {//IOS        var touchstart = true;        window.location = "/touchstart";     //改变URL  注意：要使用"/"分隔符     }    function postStr() {//IOS        return image.src;    }

// 当加载完网页取到imageurl
- (void)webViewDidFinishLoad:(UIWebView *)webView{    _urlString = [_myWebView stringByEvaluatingJavaScriptFromString:@"postStr();"];    NSLog(@"%@",_urlString);}// 调用次序 - shouldStart->FinishLoad->回调block函数
- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType{    if ([request.mainDocumentURL.relativePath isEqualToString:@"/touchstart"]) {        UIImageFromURL( [NSURL URLWithString:_urlString], ^( UIImage * image )                       {                           UIImageWriteToSavedPhotosAlbum( image, self, @selector( onSaveComplete:didFinishSavingWithError:contextInfo: ), nil );                       }, ^(void){                           NSLog(@"error!");                       });        return false;    }    return  true;}void UIImageFromURL( NSURL * URL, void (^imageBlock)(UIImage * image), void (^errorBlock)(void) ){    dispatch_async( dispatch_get_global_queue( DISPATCH_QUEUE_PRIORITY_DEFAULT, 0 ), ^(void)                   {                       NSData * data =http://www.mamicode.com/ [[NSData alloc] initWithContentsOfURL:URL];                       UIImage * image = [[UIImage alloc] initWithData:data];                       dispatch_async( dispatch_get_main_queue(), ^(void){                           if( image != nil )                           {                               imageBlock( image );                           } else {                               errorBlock();                           }                       });                   });}