SQL bigint哈希匹配c#int64哈希

Question

我正在尝试创建一个通用散列alogrithim,它将字符串散列为64位int.

我能够正确地散列字符串:sql:

select  
    convert
    (
        varchar(64),
        HASHBYTES
        (
            'SHA1',
            'google.com'
        ),
        2
    )

回报 BAEA954B95731C68AE6E45BD1E252EB4560CDC45

C#

    System.Security.Cryptography.SHA1 c = System.Security.Cryptography.SHA1.Create();
    System.Text.StringBuilder sb = new StringBuilder();
    byte[] b = c.ComputeHash(Encoding.UTF8.GetBytes("google.com"));
    for (int i = 0; i < b.Length;i++ )
    {
        byte by = b[i];
        sb.Append(by.ToString("x2").ToUpper());
    }

    return sb.ToString();

retruns BAEA954B95731C68AE6E45BD1E252EB4560CDC45

但是,当我转换为bigint/long时,值不匹配:sql:

select  
    convert
    (
        bigint,
        HASHBYTES
        (
            'SHA1',
            'google.com'
        )
    )

回报 2172193747348806725

C#:

    System.Security.Cryptography.SHA1 c = System.Security.Cryptography.SHA1.Create();
    byte[] b = c.ComputeHash(Encoding.UTF8.GetBytes("google.com"));
    return BitConverter.ToInt64(b, 0);

回报 7501998164347841210

有关如何使这些数字匹配的任何想法？

Answer 1

您的SQL bigint占用最后8个字节,而c#实现占用前8个字节(并且因为它在小端上运行而反转它们).

在C#中取适当的数组范围并将其反转.那你应该没问题.

做了一些编码:

System.Security.Cryptography.SHA1 c = System.Security.Cryptography.SHA1.Create();
byte[] b = c.ComputeHash(Encoding.UTF8.GetBytes("google.com"));
long value = BitConverter.ToInt64(b, 12);
value = IPAddress.HostToNetworkOrder(value);

Debug.WriteLine(value);
// writes 2172193747348806725