ios - 在 iOS 设备上读取 csv 文件时出错

Question

我创建了一个保存为 csv 文件的应用程序，该应用程序在 iOS 模拟器中运行良好，可以读写。当我将应用程序加载到 iOS 设备时，它没有数据。

- (IBAction)saveInfo:(id)sender {
    NSString *resultLine = [NSString stringWithFormat:@"%@,%@,%@\n",
                            self.food.text,
                            self.movies.text,
                            self.channel.text];
    NSArray *path= NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *docPath = [path objectAtIndex:0];
    //resultView.text = docPath;

    NSString *filename = [docPath stringByAppendingString:@"result.csv"];
    resultView.text = filename;

    if (![[NSFileManager defaultManager] fileExistsAtPath:filename])
    {
        [[NSFileManager defaultManager] createFileAtPath:filename contents:nil attributes:nil];
    }
    NSFileHandle *fileHandle = [NSFileHandle fileHandleForUpdatingAtPath:filename];
    [fileHandle seekToEndOfFile];
    [fileHandle writeData:[resultLine dataUsingEncoding:NSUTF8StringEncoding]];
    [fileHandle closeFile];
    self.food.text = nil;
    self.movies.text = nil;
    self.channel.text =nil;
    NSLog(@"Info saved");


}


- (IBAction)viewInfo:(id)sender {
    NSArray *path= NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *docPath = [path objectAtIndex:0];
    NSString *filename = [docPath stringByAppendingString:@"result.csv"];

    NSString *fileContent=[NSString stringWithContentsOfFile:filename encoding:NSUTF8StringEncoding error:nil];

    resultView.text = fileContent;

}

Answer 1

您构建的路径不正确。使用:

NSArray *path= NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *docPath = [path objectAtIndex:0];
NSString *filename = [docPath stringByAppendinPathComponent:@"result.csv"];

您的代码导致路径类似于 <path to app bundle>/Documentsresult.csv在设备上，您无法写入应用程序包。