demo功能：点击网页中的图片，图片放大效果的demo。iphone6.1 测试通过。

demo说明：通过webview的委托事件shouldStartLoadWithRequest来实现。

demo截屏：

demo主要代码：

 

#pragma mark -#pragma mark UIWebViewDelegate- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType{    //将url转换为string	NSString *picName = [[request URL] absoluteString];	NSLog(@"picName is %@",picName);    //hasPrefix 判断创建的字符串内容是否以pic:字符开始	if ([picName hasPrefix:@"pic:"]) {		[self showBigImage:[picName substringFromIndex:4]];		return NO;	}else {		return YES;	}}#pragma mark -//显示大图片-(void)showBigImage:(NSString *)imageName{	//创建灰色透明背景，使其背后内容不可操作	UIView *bgView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 460)];	[bgView setBackgroundColor:[UIColor colorWithRed:0.3 											   green:0.3 												blue:0.3 											   alpha:0.7]];	[self.view addSubview:bgView];	[bgView release];		//创建边框视图	UIView *borderView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, BIG_IMG_WIDTH+16, BIG_IMG_HEIGHT+16)];	//将图层的边框设置为圆脚     borderView.layer.cornerRadius = 8; 	borderView.layer.masksToBounds = YES;     //给图层添加一个有色边框 	borderView.layer.borderWidth = 8; 	borderView.layer.borderColor = [[UIColor colorWithRed:0.9													green:0.9													 blue:0.9													alpha:0.7] CGColor];	[borderView setCenter:bgView.center];	[bgView addSubview:borderView];	[borderView release];		//创建关闭按钮	UIButton *closeBtn = [UIButton buttonWithType:UIButtonTypeCustom];	[closeBtn setImage:[UIImage imageNamed:@"close.png"] forState:UIControlStateNormal];	[closeBtn addTarget:self action:@selector(removeBigImage:) forControlEvents:UIControlEventTouchUpInside];	NSLog(@"borderview is %@",borderView);	[closeBtn setFrame:CGRectMake(borderView.frame.origin.x+borderView.frame.size.width-20, borderView.frame.origin.y-6, 26, 27)];	[bgView addSubview:closeBtn];		//创建显示图像视图	UIImageView *imgView = [[UIImageView alloc] initWithFrame:CGRectMake(8, 8, BIG_IMG_WIDTH, BIG_IMG_HEIGHT)];	[imgView setImage:[UIImage imageNamed:imageName]];	[borderView addSubview:imgView];	[imgView release];}

demo下载地址：