ios NSData dataWithContentsOfFile 返回 null
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NSData dataWithContentsOfFile returning null
提问by user3129278
I am trying to fetching a JSONfile which exist in my xcoderesources using this code
我正在尝试使用此代码获取资源JSON中存在的文件xcode
-(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 return me this link of file path
路径返回我这个文件路径链接
/Users/astutesol/Library/Application Support/iPhone Simulator/6.0/Applications/A4E1145C-500C-4570-AF31-9E614FDEADE4/The Gym Factory.app/classes.json
but when I log fileDatait return me null. I don't know where I am doing mistake.
但是当我登录fileData它时，它会返回给我null。我不知道我在哪里做错了。
回答by TheAmateurProgrammer
Instead of appending the path, use pathForResource:ofType:, so
而不是附加路径，使用pathForResource:ofType:，所以
NSString *str=[[NSBundle mainBundle] pathForResource:@"classes" ofType:@"json"];
NSData *fileData = [NSData dataWithContentsOfFile:str];
回答by JeremyP
It's failed to read your file for some reason. Use -dataWithContentsOfFile:options:error:to find out why.
由于某种原因无法读取您的文件。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
}
回答by TtheTank
NSString *filePath = [[NSBundle mainBundle] pathForResource:@"MyFile" ofType:@"txt"];
NSData *myData = [NSData dataWithContentsOfFile:filePath];
回答by Kevin ABRIOUX
There is the solution for Swift 3 :
Swift 3 有解决方案：
//create a fil's path, decompose name and extension
let path = Bundle.main.path(forResource: "anim-gif-1", ofType: "gif")
//get the data asociated to this file
let file = NSData(contentsOfFile: path!)
回答by Manthan
You need to use pathforResource with resourcetype and check if there is data in your file.
您需要使用 pathforResource 和 resourcetype 并检查文件中是否有数据。
That should not be nil.
那不应该是零。
回答by Code Hunter
You can follow this to get NSData from your document directory
您可以按照此从您的文档目录中获取 NSData
NSString *stringPath = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)objectAtIndex:0]stringByAppendingPathComponent:@"YOUR_FOLDER_NAME"];
stringPath = [stringPath stringByAppendingPathComponent:@"JSON_FILE_NAME.json"];
NSLog(@"stringpath %@",stringPath);
NSData *fileData = [NSData dataWithContentsOfFile:stringPath];
Hope this will work for you.
希望这对你有用。
