什么是signingCredentials jwt asp.net核心中的密钥长度

Question

 public static string GenerateToken(string Username)
    {
        var claimsdata = new[] { new Claim(ClaimTypes.Name, Username) };
        var key = new SymmetricSecurityKey(Encoding.UTF8.GetBytes("qwertyuioplkjhgfdsazxcvbnmqwertlkjfdslkjflksjfklsjfklsjdflskjflyuioplkjhgfdsazxcvbnmmnbv"));
        var signInCred = new SigningCredentials(key, SecurityAlgorithms.HmacSha384Signature);
        var token = new JwtSecurityToken(
            issuer: "mysite",
            audience: "mysite",
            expires: DateTime.Now.AddMinutes(60),
            claims: claimsdata,
            signingCredentials: signInCred
            );
        var tokenString = new JwtSecurityTokenHandler().WriteToken(token);
        return tokenString;
    }

//密钥长度为88个字符。如果我将其减少到少于16个字符，则会出现异常：

System.ArgumentOutOfRangeException：'IDX10603：解密失败。尝试过的键：“ [PII隐藏]”。捕获到异常：“ [PII隐藏]”。令牌：“ [PII隐藏]”

Answer 1

sha256中的最小长度（16个字符），因为它们是256个十六进制位，则256/16 = 16