在iPhone中读写文件

写入文件:

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

// the path to write file
NSString *myFile = [documentsDirectory stringByAppendingPathComponent:@"myFile"];

[data writeToFile:myFile atomically:YES];

读取文件:

NSString *filePath = [[NSBundle mainBundle] pathForResource:@"MyFile" ofType:@"txt"];  
NSData *myData = [NSData dataWithContentsOfFile:filePath];  
if (myData) {  
    // do something useful  
}