Question

我正在撰写阅读iOS应用的文章。

我在匹配文件夹中有.json个文件，名为Data.json 我无法将数据写入其中。

这是我的代码：

- (void)writeJsonToFile {
    //applications Documents dirctory path
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];

    //live json data url
    NSString *stringURL = ysURL;
    NSURL *url = [NSURL URLWithString:stringURL];
    NSData *urlData = [NSData dataWithContentsOfURL:url];
    //file to write to

    NSString *filePath = [NSString stringWithFormat:@"%@/%@", documentsDirectory, @"Data.json"];
    //attempt to download live data
    if (urlData) {

        [urlData writeToFile:filePath atomically:YES];
    }
    //copy data from initial package into the applications Documents folder
    else {
        //file to write to

        NSString *filePath = [NSString stringWithFormat:@"%@/%@",  documentsDirectory, @"Data.json"];
        //file to copy from
        NSString *json = [[NSBundle mainBundle] pathForResource:@"Data" ofType:@"json" inDirectory:@"/match/Data.json"];
        NSData *jsonData = [NSData dataWithContentsOfFile:json options:kNilOptions error:nil];

        //write file to device
        [jsonData writeToFile:filePath atomically:YES];
    }
}

Answer 1

你可以告诉我们你有关问题的更多信息吗？

1）您不必重新定义其他地方的filePath，因为您之前已经这样做了。

NSString *filePath = [NSString stringWithFormat:@"%@/%@", documentsDirectory, @"Data.json"];

你应该使用stringByAppendingPathComponent自动添加你需要的/：

NSString *filePath = [documentsDirectory stringByAppendingPathComponent:@"Data.json]

2）你确定你的Data.json包含在你的项目中吗？你有没有？

    NSString *json = [[NSBundle mainBundle] pathForResource:@"Data" ofType:@"json" inDirectory:@"/match/Data.json"];

3）对于无法加载的问题：</Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator7.1.sdk/System/Library/AccessibilityBundles/CertUIFramework.axbundle> (not loaded)

Cannot find executable for CFBundle CertUIFramework.axbundle

Answer 2

尝试使用NSStrings方法编写文件，并检查错误代码：

NSURL *fileUrl = [[NSBundle mainBundle] URLForResource: @"Data" withExtension:@"json"];
NSError * error;
[json writeToURL:fileUrl atomically:YES encoding:NSUTF8StringEncoding error:&error];
NSLog(@"%@",error.localizedDescription);

如何将JSON数据存储在文件中？

2 个答案: