你怎么能产生相同的MD5的hashCode C＃和Java？ [英] How can you generate the same MD5 Hashcode in C# and Java?

问题描述

我有一个生成C＃中的MD5哈希这样的功能：

I have a function that generates a MD5 hash in C# like this:

MD5 md5 = new MD5CryptoServiceProvider();
byte[] result = md5.ComputeHash(data);
StringBuilder sb = new StringBuilder();
for (int i = 0; i < result.Length; i++)
{
    sb.Append(result[i].ToString("X2"));
}
return sb.ToString();

在java中我的功能看起来像这样：

In java my function looks like this:

MessageDigest m = MessageDigest.getInstance("MD5");
m.update(bytes,0,bytes.length);

String hashcode = new BigInteger(1,m.digest()).toString(16);
return hashcode;

尽管C＃代码生成：02945C9171FBFEF0296D22B0607D522Djava的代码生成：5a700e63fa29a8eae77ebe0443d59239

While the C# code generates: "02945C9171FBFEF0296D22B0607D522D" the java codes generates: "5a700e63fa29a8eae77ebe0443d59239".

有没有一种方法来生成相同的字节组相同的MD5哈希值

Is there a way to generate the same md5 hash for the same bytearray?

在需求：

这是在Java中testcode：

This is the testcode in java:

File file = new File(System.getProperty("user.dir") + "/HashCodeTest.flv");
byte[] bytes = null;
try {
    bytes = FileUtils.getBytesFromFile(file);
} catch (IOException e) {
    fail();
}
try {
    generatedHashCode = HashCode.generate(bytes);
} catch (NoSuchAlgorithmException e) {
    fail();
}

这是我在C＃代码

and this is my code in C#

var blob = GetBlobByHttpPostedFile(httpPostedFile);
var hashCode = Md5Factory.ConvertByteArray(blob);

private static byte[] GetBlobByHttpPostedFile(HttpPostedFile httpPostedFile)
{
    var contentLength = httpPostedFile.ContentLength; 
    var result = new byte[contentLength];
    var inputStream = httpPostedFile.InputStream;
    inputStream.Read(result, 0, contentLength);

    return result;
}

干杯

Cheers

推荐答案

这应该是罚款 - 尽管你可以让Java代码更简单，只需调用

That should be fine - although you could make the Java code simpler by just calling

byte[] digest = m.digest(bytes);

而不是调用更新然后消化。

您的绝对保证的你在这两种情况下得到了相同的数据？你可以张贴出具有相同的硬编码数据没有这个示例程序

Are you absolutely sure you've got the same data in both cases? Could you post sample programs showing this failing with the same hard-coded data?

编辑：这里是那种测试，我在想的。这两个程序产生相同的结果：

Here's the sort of test I was thinking of. These two programs give the same result:

C＃：

using System;
using System.Security.Cryptography;
using System.Text;

class Test
{
    static void Main()
    {
        byte[] bytes = { 0x35, 0x24, 0x76, 0x12 };
        MD5 md5 = new MD5CryptoServiceProvider();
        byte[] result = md5.ComputeHash(bytes);
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < result.Length; i++)
        {
            sb.Append(result[i].ToString("x2"));
        }
        Console.WriteLine(sb);
    }
}

Java的：

Java:

import java.math.BigInteger;
import java.security.MessageDigest;

public class Test
{
    public static void main(String[] args) throws Exception
    {
        byte[] bytes = { 0x35, 0x24, 0x76, 0x12 };
        MessageDigest m = MessageDigest.getInstance("MD5");
        byte[] digest = m.digest(bytes);
        String hash = new BigInteger(1, digest).toString(16);
        System.out.println(hash);
    }
}

这篇关于你怎么能产生相同的MD5的hashCode C＃和Java？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！