如何转换列表<Claim>到字典<string,object> ?

Question

I'm getting my claims to put on jwt token

Get Valid Claims and Generate Jwt Token

var claims = await GetValidClaims(users);
Token = GenerateJwtToken(users, claims);

GenerateJwtToken Method

private string GenerateJwtToken(ApplicationUser user, List<Claim> claims)
{
    var dicClaim = new Dictionary<string,object>();
    ...
    var tokenDescriptor = new SecurityTokenDescriptor
    {
        Claims = dicClaim,   // <<<<<<<<<< this Claims is Dictionary<string,object>
        ...
    }
}

GetValidClaims Method

private async Task<List<Claim>> GetValidClaims(ApplicationUser user)
{
    IdentityOptions _options = new IdentityOptions();
    var claims = new List<Claim>
    {
        new Claim(JwtRegisteredClaimNames.Sub, user.UserName),
        new Claim(_options.ClaimsIdentity.UserIdClaimType, user.Id.ToString()),
        new Claim(_options.ClaimsIdentity.UserNameClaimType, user.UserName)
    };
    var userClaims = await _userManager.GetClaimsAsync(user);
    var userRoles = await _userManager.GetRolesAsync(user);
    claims.AddRange(userClaims);
    foreach (var userRole in userRoles)
    {
        claims.Add(new Claim(ClaimTypes.Role, userRole));
        var role = await _roleManager.FindByNameAsync(userRole);
        if (role != null)
        {
            var roleClaims = await _roleManager.GetClaimsAsync(role);
            foreach (Claim roleClaim in roleClaims)
            {
                claims.Add(roleClaim);
            }
        }
    }
    return claims;
}

At this line: Claims = dicClaim, // <<<<<<<<<< this Claims is Dictionary<string,object>

But I don't know how to convert List to Dictionary

I already tried something like this:

claims.ToDictionary(x=>x,x=>x.Value)

claims.ToDictionary(x=>x.Value,x=>x)

Lib SecurityTokenDescriptor

Answer 1

In order to create a dictionary we have to define a unique Key for it. Assuming that

1. We want our key to be say, Type or at least start from Type
2. Claims can be repeated

we can solve it like this:

1. Group all claims by Type (desired key)
2. If there's only 1 claim in a group, use Value as Key
3. If not, let's generate Type_1 , Type_2 , ..., Type_N Key s

Code

var dicClaim = claims
  .GroupBy(claim => claim.Type) // Desired Key
  .SelectMany(group => group
     .Select((item, index) => group.Count() <= 1
        ? Tuple.Create(group.Key, item) // One claim in group
        : Tuple.Create($"{group.Key}_{index + 1}", item) // Many claims
      )) 
  .ToDictionary(tuple => tuple.Item1, tuple => tuple.Item2); 

If in case of repeated claims you want to get, say, the Last one only, you can do it with the code:

 var dicClaim = claims
   .GroupBy(claim => claim.Type) // Desired Key
   .ToDictionary(group => group.Key, group => group.Last());