Metro获取StorageFile的base64字符串

Question

我需要File Picker选择的文件的base64字符串。

//file is a StorageFile 

FileRandomAccessStream stream = (FileRandomAccessStream)await file.OpenAsync(FileAccessMode.ReadWrite); 

using (MemoryStream ms = new MemoryStream()) 
{ 
    Stream ss1 = stream.AsStream(); ; 
    s1.CopyTo(ms); 

} 
byteArray = ms.ToArray(); 
string imageStringSixtyfour = Convert.ToBase64String(byteArray); 
if (imageStringSixtyfour != null) 
return imageStringSixtyfour; 

返回的字符串总是空的，有什么想法？大多数在线的例子是与不是的W8平台一部分的类

Answer 1

试试这个

private async Task<string> StorageFileToBase64(StorageFile file) 
{ 
    string Base64String = ""; 

    if (file != null) 
    { 
     IRandomAccessStream fileStream = await file.OpenAsync(FileAccessMode.Read); 
     var reader = new DataReader(fileStream.GetInputStreamAt(0)); 
     await reader.LoadAsync((uint)fileStream.Size); 
     byte[] byteArray = new byte[fileStream.Size]; 
     reader.ReadBytes(byteArray); 
     Base64String = Convert.ToBase64String(byteArray); 
    } 

    return Base64String; 
}