NSData dataWithContentsOfFile返回null

Question

我正在尝试使用此代码获取JSON存在于我的xcode资源中的文件

-(void)readJsonFiles
{
    NSString *str=[[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"classes.json"];
    NSLog(@"Path: %@", str);
    NSData *fileData = [NSData dataWithContentsOfFile:str];
    NSLog(@"Data: %@", fileData);
    SBJsonParser *parser = [[SBJsonParser alloc] init] ;
    NSDictionary *jsonObject = [parser objectWithData:fileData];
    NSLog(@"%@", jsonObject);
}

path返回文件路径的这个链接

/Users/astutesol/Library/Application Support/iPhone Simulator/6.0/Applications/A4E1145C-500C-4570-AF31-9E614FDEADE4/The Gym Factory.app/classes.json

但是当我登录时fileData它会归还给我null.我不知道我在哪里做错了.

Answer 1

而不是追加路径,使用pathForResource:ofType:,所以

NSString *str=[[NSBundle mainBundle] pathForResource:@"classes" ofType:@"json"];

NSData *fileData = [NSData dataWithContentsOfFile:str];

Answer 2

由于某种原因，它无法读取您的文件。使用-dataWithContentsOfFile:options:error:找出原因。

NSError* error = nil;
NSData *fileData = [NSData dataWithContentsOfFile:str options: 0 error: &error];
if (fileData == nil)
{
   NSLog(@"Failed to read file, error %@", error);
}
else
{
    // parse the JSON etc
}

Answer 3

NSString *filePath = [[NSBundle mainBundle] pathForResource:@"MyFile" ofType:@"txt"];  
NSData *myData = [NSData dataWithContentsOfFile:filePath];