///根据地址 获取文件类型
+(NSString *)mimeType:(NSURL *)url{NSURLRequest *request = [NSURLRequest requestWithURL:url];NSURLResponse *response = [[NSURLResponse alloc] init];[NSURLConnection sendSynchronousRequest:request returningResponse:&response error:nil];return response.MIMEType;
}
/// 根据文件名称、或包含名称的路径，获取其mimetype
/// - Parameter path: 文件名称、或包含名称的路径
+ (NSString *)mimeTypeForName:(NSString *)path{// [path pathExtension] 获得文件的后缀名 MIME类型字符串转化为UTI字符串CFStringRef UTI = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, (__bridge CFStringRef)[path pathExtension], NULL);// UTI字符串转化为后缀扩展名CFStringRef MIMEType = UTTypeCopyPreferredTagWithClass (UTI, kUTTagClassMIMEType);CFRelease(UTI);// application/octet-stream，此参数表示通用的二进制类型。if (!MIMEType) {return @"application/octet-stream";}return (__bridge NSString *)(MIMEType);
}
/// 根据文件data获取
+(NSString *)mimeTypeForData:(NSData *)data{uint8_t c;[data getBytes:&c length:1];switch (c){case 0xFF:return @"image/jpeg";case 0x89:return @"image/png";case 0x47:return @"image/gif";case 0x49:case 0x4D:return @"image/tiff";case 0x25:return @"application/pdf";case 0xD0:return @"application/vnd";case 0x46:return @"text/plain";}return @"";
}
)
