为什么我的文件没有保存？

Question

我正在使用一些代码从 UIWebView 保存 png 文件。它不起作用，按下“保存”按钮时没有任何反应。日志中没有出现任何内容，除了“正在保存文件...”，它只是为了测试它是否在 Interface Builder 中正确链接（确实如此）。

这是我正在使用的代码：

-(IBAction)saveFile 
{ 

NSLog(@"Saving File...");

NSURL *requestedURL = [webView.request URL]; 

if([[requestedURL pathExtension] isEqualToString:@"png"]) 
{ 
    NSData *fileData = [[NSData alloc] initWithContentsOfURL:requestedURL]; 
    //Store the data locally 
    NSString *resourceDocPath = [[NSString alloc] initWithString:[[[[NSBundle mainBundle] resourcePath]     
stringByDeletingLastPathComponent] stringByAppendingPathComponent:@"Documents"]]; 

    NSString *filePath = [resourceDocPath stringByAppendingPathComponent:[requestedURL lastPathComponent]]; 

    NSError *error = nil; 
    [fileData writeToFile:filePath options:NSDataWritingFileProtectionComplete error:&error]; 

    if(error != nil) { 
        // Failed to write the file 
        NSLog(@"Failed to write file: %@", [error description]); 
    } else { 
        UIAlertView *filenameAlert = [[UIAlertView alloc] initWithTitle:@"File saved" message:[NSString  
stringWithFormat:@"The file %@ has been saved", [requestedURL lastPathComponent]] delegate:self cancelButtonTitle:@"OK" 
otherButtonTitles:nil]; 

        [filenameAlert show]; 
        [filenameAlert release]; 
    } 
} 

Answer 1

您似乎尝试写入 mainBundle 的文件位置（这在设备上是不允许/不可能的）。尝试使用

查找文档目录

NSArray* paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, 
NSUserDomainMask, YES); 
NSString* resourceDocPath = [paths objectAtIndex:0];