如何将我的照片从 tmp 目录文件夹保存到 xamarin iOS 中的库/文档文件夹

Question

I want to save my photo from the temp folder to the library or document folder in Xamarin IOS. I use iPhone Simulator for that and Xamarin iOS native for my development. Firstly, I get the URL path then I change to the real path. So far, I got the real path:

NSUrl myFileUrl = new NSUrl(ImageValue);
            Console.WriteLine(myFileUrl.AbsoluteString);
            FromGalleryPath= myFileUrl.Path;

But the result of the path is

.../Application/xxx/tmp/5B4AFD16E192.jpeg

I don't want to store my image in the tmp --> Application/xxx/tmp/ because, every time when I restart my emulator then the picture gone? How can I save my image into the library/ document folder and how to retrieve back the path from the library/ document folder?

I've searched on the internet but, still no idea. Can anyone help me?

Thank in advance.

Answer 1

Using NSSearchPathForDirectoriesInDomains the same as native code can get the path.After searching, NSSearchPath can achieve that. Have a try with follow code to accesee Library/ path:

Create a static class NSSearchPath :

public static class NSSearchPath
{
    public static string[] GetDirectories(NSSearchPathDirectory directory, NSSearchPathDomain domainMask, bool expandTilde = true)
    {
        return NSArray.StringArrayFromHandle(NSSearchPathForDirectoriesInDomains((nuint)(ulong)directory, (nuint)(ulong)domainMask, expandTilde));
    }

    [DllImport(Constants.FoundationLibrary)]
    static extern IntPtr NSSearchPathForDirectoriesInDomains(nuint directory, nuint domainMask, bool expandTilde);
}

Uesd as follow:

string[] paths = NSSearchPath.GetDirectories(NSSearchPathDirectory.LibraryDirectory, NSSearchPathDomain.All);
Console.WriteLine(paths[0]);

Output Log:

2020-05-20 13:52:11.254843+0800 AppIOS2[4340:108912] /Users/xxxx/Library/Developer/CoreSimulator/Devices/4C2C6DD2-3D42-46EA-8078-D6E0B851AEDD/data/Containers/Data/Application/DB913987-0E55-4603-8993-ED7B3F83CF85/Library

Reference docs: https://docs.microsoft.com/en-us/xamarin/ios/app-fundamentals/file-system#application-directories