- 加载外部链接：
NSURL *url = [NSURL URLWithString:@"https://www.apple.com"];
NSURLRequest *req = [NSURLRequest requestWithURL:url];
[self.webview loadRequest:req];
- 加载本地资源：
NSString *htmlFile = [[NSBundle mainBundle] pathForResource:@"CrazyDrag" ofType:@"html"];
NSData *htmlData = [NSData dataWithContentsOfFile:htmlFile];
NSURL *baseURL = [NSURL fileURLWithPath:[[NSBundle mainBundle] bundlePath]];
[self.webview loadData:htmlData MIMEType:@"text/html" textEncodingName:@"UTF-8" baseURL:baseURL];
