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C# 将Xamarin图像保存到文件_C#_File_Xamarin_Photo - Fatal编程技术网

C# 将Xamarin图像保存到文件

C# 将Xamarin图像保存到文件,c#,file,xamarin,photo,C#,File,Xamarin,Photo,您好,我正在尝试将用户选择的图像保存到文件中,以便稍后将其上载到我的mySQL数据库 所以我有这个代码: var result = await MediaPicker.PickPhotoAsync(new MediaPickerOptions { Title = "Please pick a selfie" }); var stream = await result.OpenReadAsync(); resultImage.Source = ImageSource.

您好,我正在尝试将用户选择的图像保存到文件中,以便稍后将其上载到我的mySQL数据库

所以我有这个代码:

var result = await MediaPicker.PickPhotoAsync(new MediaPickerOptions
{
    Title = "Please pick a selfie"
});

var stream = await result.OpenReadAsync();
resultImage.Source = ImageSource.FromStream(() => stream);

string path = Environment.GetFolderPath(Environment.SpecialFolder.Personal);
string filename = Path.Combine(path, "myfile");

using (var streamWriter = new StreamWriter(filename, true))
{
    streamWriter.WriteLine(GetImageBytes(stream).ToString());
}

using (var streamReader = new StreamReader(filename))
{
    string content = streamReader.ReadToEnd();
    System.Diagnostics.Debug.WriteLine(content);
}
下面是GetImageBytes(..)函数:

private byte[] GetImageBytes(Stream stream)
{
    byte[] ImageBytes;
    using (var memoryStream = new System.IO.MemoryStream())
    {
        stream.CopyTo(memoryStream);
        ImageBytes = memoryStream.ToArray();
    }
    return ImageBytes;
}
代码可以工作,它创建一个文件,但不保存图像。相反,它保存“System.Bytes[]”。它保存对象的名称,而不是对象的内容


任何帮助都将不胜感激。谢谢

将字节数组编码为base64字符串,然后将其存储在文件中:

private string GetImageBytesAsBase64String(Stream stream)
    {
        var imageBytes;
        using (var memoryStream = new System.IO.MemoryStream())
        {
            stream.CopyTo(memoryStream);
            imageBytes = memoryStream.ToArray();
        }
        return Convert.ToBase64String(imageBytes);
    }

如果以后需要从文件中检索图像字节,可以使用相应的Convert.FromBase64String(imageBytesAsBase64String)方法。

StreamWriter
用于写入格式化字符串,而不是二进制数据。试试这个

File.WriteAllBytes(filename,GetImageBytes(stream));
成功了!多谢各位