获取文件名 通过URL地址

+ (NSString *)getFileName:(NSString *)urlString{
    //1、lastPathComponent
    NSString *fileName = [urlString lastPathComponent];
    //2、NSRange尾部截取法
    NSRange range = [urlString rangeOfString:@"/"options:(NSBackwardsSearch)];
    if(range.location == NSNotFound) {
        fileName = urlString;
    } else {
        fileName = [urlString substringFromIndex:range.location+1];
    }
    return fileName;
}