Question

我在我的应用程序中使用PHAsset，我需要将图像和视频上传到api，因为我需要mime类型的图像和视频。在iOS的早期版本中，我使用了以下代码，但在iOS 8中，我不知道如何获取mimetype我尝试过查看苹果PHAsset编程指南但无法找到它。

ALAssetRepresentation *representation = [asset defaultRepresentation];
NSString *mimeType = (__bridge_transfer NSString *)UTTypeCopyPreferredTagWithClass
        ((__bridge CFStringRef)[representation UTI], kUTTagClassMIMEType);

寻找任何指导。

Answer 1

PHContentEditingInput拥有财产uniformTypeIdentifier。您可以在the documentation找到更多信息。

@import MobileCoreServices.UTType;

...

PHAsset *asset = ...
PHContentEditingInputRequestOptions *options = ...
[asset requestContentEditingInputWithOptions:options completionHandler:^(PHContentEditingInput *contentEditingInput, NSDictionary *info) {
    NSString *MIME = (__bridge NSString *)UTTypeCopyPreferredTagWithClass((__bridge CFStringRef)contentEditingInput.uniformTypeIdentifier, kUTTagClassMIMEType);
}];

Answer 2

您还可以从PHContentEditingInput类中找到uniformTypeIdentifier。为了这;使用PHAsset的requestContentEditingInput函数

别忘了导入MobileCoreServices

示例Swift 3.1代码：

import MobileCoreServices


let options = PHContentEditingInputRequestOptions()
options.isNetworkAccessAllowed = true //for icloud backup assets

let asset : PHAsset = .....  //sampleAsset
asset.requestContentEditingInput(with: options) { (contentEditingInput, info) in
    if let uniformTypeIdentifier = contentEditingInput?.uniformTypeIdentifier {

        //check type here
        if uniformTypeIdentifier == (kUTTypeGIF as String) {
            debugPrint("This asset is a GIF")
        }

    }
}

Answer 3

使用PHImageManager的requestImageDataForAsset方法。在它的resultBlock中，该方法返回资产的UTI-Type。

Answer 4

我最终获得了PHAsset的MIME类型，如下所示（iOS 9 +）：

1  is divided by 1
2  is divided by 1
2  is divided by 2
3  is divided by 1
3  is divided by 3
4  is divided by 1
4  is divided by 2
4  is divided by 4
5  is divided by 1
5  is divided by 5
6  is divided by 1
6  is divided by 2
6  is divided by 3
6  is divided by 6
7  is divided by 1
7  is divided by 7
8  is divided by 1
8  is divided by 2
8  is divided by 4
8  is divided by 8
9  is divided by 1
9  is divided by 3
9  is divided by 9

将事物与呼唤相结合/加以改进：

如果无法导出mimeType，我选择默认为image / jpeg。
假设第一个资源是适当的资源。多资源资产（实时照片等）可能并非如此。
我尚未针对iCloud中需要下载的资产测试其运行方式/是否按预期工作。

如果有人对＃2或＃3有见识，将不胜感激。当我发现更多信息时，我会更新我的答案。

如何使用PHAsset在iOS 8中获取图像或视频的MIME类型？

4 个答案: