计算文件大小

     CGFloat size = 0.0;

     // 找到需要计算大小文件夹的全路径  
     NSString *path = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES).lastObject;

     NSFileManager *manager = [NSFileManager defaultManager];
     NSArray *arr = [manager subpathsAtPath:path];
     for (NSString *str  in arr) {
         NSString *subPath = [path stringByAppendingPathComponent:str];
         NSString *sizeStr = [manager attributesOfItemAtPath:subPath error:nil][NSFileSize];
         size += sizeStr.floatValue;
       }

     NSString *str = [NSString stringWithFormat:@"%.2fM", size / 1000000];

封装工具类另一种

#import "NSString+XMGExtension.h"

@implementation NSString (Extension)
- (unsigned long long)fileSize
{
    // 总大小
    unsigned long long size = 0;

    // 文件管理者
    NSFileManager *mgr = [NSFileManager defaultManager];

    // 是否为文件夹
    BOOL isDirectory = NO;

    // 路径是否存在
    BOOL exists = [mgr fileExistsAtPath:self isDirectory:&isDirectory];
    if (!exists) return size;

    if (isDirectory) { // 文件夹
        // 获得文件夹的大小  == 获得文件夹中所有文件的总大小
        NSDirectoryEnumerator *enumerator = [mgr enumeratorAtPath:self];
        for (NSString *subpath in enumerator) {
            // 全路径
            NSString *fullSubpath = [self stringByAppendingPathComponent:subpath];
            // 累加文件大小
            size += [mgr attributesOfItemAtPath:fullSubpath error:nil].fileSize;
        }
    } else { // 文件
        size = [mgr attributesOfItemAtPath:self error:nil].fileSize;
    }

    return size;
}

删除文件NSFileManager

- (BOOL)removeItemAtPath:(NSString *)path error:(NSError **)error;