以后如何使用UIWebView显示下载的文件?

您可以在完成下载后以字符串形式读取本地文件,然后使用UIWebView的 loadHTMLString:baseURL: baseURL :

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 
NSString *yourFolderPath = [[paths objectAtIndex:0] stringByAppendingPathComponent: @"yourFolder"];
NSString *filePath = [yourFolderPath stringByAppendingPathComponent: @"yourFile.htm"];
NSString *fileContents = [NSString stringWithContentsOfFile: filePath];
NSURL *baseURL = [NSURL fileURLWithPath: yourFolderPath];
[yourWebView loadHTMLString: fileContents baseURL: baseURL];