ios plist文件和加载到内存时占用空间大小

plist文件以文本形式存储，一个字符占用一个字节，外加plist文件的头部，占用空间就是所有的字符数。

加载到内存所占空间与文件大小一致。

比如下方一个字符串是300个字符。10000个对象存储到文件中，文件大小为3.2MB。加载到内存所占空间也是3.2MB

- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
NSMutableArray *array = [[NSMutableArray alloc] init];

for (int i=0; i<10000; i++) {
[array addObject:@"adsjadslkjfksdajfklasjdkfkalsdklfadsjadslkjfksdajfklasjdkfkalsdklfadsjadslkjfksdajfklasjdkfkalsdklfadsjadslkjfksdajfklasjdkfkalsdklfadsjadslkjfksdajfklasjdkfkalsdklfadsjadslkjfksdajfklasjdkfkalsdklfadsjadslkjfksdajfklasjdkfkalsdklfadsjadslkjfksdajfklasjdkfkalsdklfadsjadslkjfksdajfklasjdkfkalsdklfa300"];
}
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *fileName = @"1.plist";
NSString *filePath = [documentsDirectory stringByAppendingPathComponent:fileName];
NSLog(@"path is : %@",filePath);
[array writeToFile:filePath atomically:YES];

NSArray *arr2 = [NSArray arrayWithContentsOfFile:filePath];
self.arr2 = arr2;
NSLog(@"");

}