.net 3.1 QueryStringRequiredAttribute

QueryStringRequiredAttribute.cs

  public class QueryStringRequiredAttribute : Attribute, IActionConstraint
  {
    public int Order => 0;
    public string Name { get; set; }

    public QueryStringRequiredAttribute(string queryStringName)
    {
      Name = queryStringName;
    }

    public bool Accept(ActionConstraintContext context)
      => context.RouteContext.HttpContext.Request.Query.ContainsKey(Name);
  }