full name c# code

fullname.cs

   public static string ToFullName(string? name, string? secoundName, string? lastName, string? secoundLastName)
    {
        string _name = string.IsNullOrEmpty(name) ? "" : $"{name.Trim()[0].ToString().ToUpper()}{name[1..]}";
        string _secoundName = string.IsNullOrEmpty(secoundName) ? "" : $"{secoundName.Trim()[0].ToString().ToUpper()}{secoundName[1..]}";
        string _lastName = string.IsNullOrEmpty(lastName) ? "" : $"{lastName.Trim()[0].ToString().ToUpper()}{lastName[1..]}";
        string _secoundLastName = string.IsNullOrEmpty(secoundLastName) ? "" : $"{secoundLastName.Trim()[0].ToString().ToUpper()}{secoundLastName[1..]}";

        return $"{_name}{(string.IsNullOrEmpty(secoundName?.Trim()) ? " " : $" {_secoundName} ")}{_lastName}{(string.IsNullOrEmpty(secoundLastName?.Trim()) ? "" : $" {_secoundLastName}")}";
    }