//在webView加载完毕后注入js样式修改图片宽高,网上很多人抄来抄去都只是更改了宽度,却没有去更改高度
-(void)webViewDidFinishLoad:(UIWebView *)webView{
NSString *js = @"function changeImgWH() { \
var imgs = document.getElementsByTagName('img'); \
for (var i = 0; i < imgs.length; ++i) {\
var img = imgs[i];\
var imgW = img.width;\
var imgH = img.height;\
var s = imgH/imgW;\
img.style.maxWidth = %f;\
img.height = img.width*s; \
} \
}";
js = [NSString stringWithFormat:js, [UIScreen mainScreen].bounds.size.width - 15];
[webView stringByEvaluatingJavaScriptFromString:js];
[webView stringByEvaluatingJavaScriptFromString:@"changeImgWH()"];
}