将文件转换为 Base64String 并再次返回

标题说明了一切:

我在 tar.gz 存档中读到的是这样的内容
将文件分成一个字节数组
将这些字节转换为 Base64字符串
将 Base64字符串转换回字节数组
将这些字节写回到一个新的 tar.gz 文件中

我可以确认这两个文件是相同的大小(下面的方法返回真) ，但我不能再提取副本版本。

我错过了什么吗？

Boolean MyMethod(){
using (StreamReader sr = new StreamReader("C:\...\file.tar.gz")) {
String AsString = sr.ReadToEnd();
byte[] AsBytes = new byte[AsString.Length];
Buffer.BlockCopy(AsString.ToCharArray(), 0, AsBytes, 0, AsBytes.Length);
String AsBase64String = Convert.ToBase64String(AsBytes);


byte[] tempBytes = Convert.FromBase64String(AsBase64String);
File.WriteAllBytes(@"C:\...\file_copy.tar.gz", tempBytes);
}
FileInfo orig = new FileInfo("C:\...\file.tar.gz");
FileInfo copy = new FileInfo("C:\...\file_copy.tar.gz");
// Confirm that both original and copy file have the same number of bytes
return (orig.Length) == (copy.Length);
}

编辑: 工作示例要简单得多(感谢@T. S.) :

Boolean MyMethod(){
byte[] AsBytes = File.ReadAllBytes(@"C:\...\file.tar.gz");
String AsBase64String = Convert.ToBase64String(AsBytes);


byte[] tempBytes = Convert.FromBase64String(AsBase64String);
File.WriteAllBytes(@"C:\...\file_copy.tar.gz", tempBytes);


FileInfo orig = new FileInfo(@"C:\...\file.tar.gz");
FileInfo copy = new FileInfo(@"C:\...\file_copy.tar.gz");
// Confirm that both original and copy file have the same number of bytes
return (orig.Length) == (copy.Length);
}

谢谢！

293244

小开

最佳答案

如果由于某种原因需要将文件转换为 base-64字符串。比如你想通过网络传递信息。.你能做到的

Byte[] bytes = File.ReadAllBytes("path");
String file = Convert.ToBase64String(bytes);

相应地，再读一遍文件:

Byte[] bytes = Convert.FromBase64String(b64Str);
File.WriteAllBytes(path, bytes);

小开

private String encodeFileToBase64Binary(File file){
String encodedfile = null;
try {
FileInputStream fileInputStreamReader = new FileInputStream(file);
byte[] bytes = new byte[(int)file.length()];
fileInputStreamReader.read(bytes);
encodedfile = Base64.encodeBase64(bytes).toString();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return encodedfile;
}

小开

VB.NET 中的另一个工作示例:

Public Function base64Encode(ByVal myDataToEncode As String) As String
Try
Dim myEncodeData_byte As Byte() = New Byte(myDataToEncode.Length - 1) {}
myEncodeData_byte = System.Text.Encoding.UTF8.GetBytes(myDataToEncode)
Dim myEncodedData As String = Convert.ToBase64String(myEncodeData_byte)
Return myEncodedData
Catch ex As Exception
Throw (New Exception("Error in base64Encode" & ex.Message))
End Try
'
End Function

小开

对于 Java，可以考虑使用 Apache Commons FileUtils:

/**
* Convert a file to base64 string representation
*/
public String fileToBase64(File file) throws IOException {
final byte[] bytes = FileUtils.readFileToByteArray(file);
return Base64.getEncoder().encodeToString(bytes);
}


/**
* Convert base64 string representation to a file
*/
public void base64ToFile(String base64String, String filePath) throws IOException {
byte[] bytes = Base64.getDecoder().decode(base64String);
FileUtils.writeByteArrayToFile(new File(filePath), bytes);
}