public bool TryGetValue(HrbcField key, out FieldCollection value)
 {
     return(content.TryGetValue(key, out value));
 }
 public IBuilder Append(string fieldAlias, FieldCollection fieldCollection)
 {
     return(Append(fieldAlias.ToField(), fieldCollection));
 }
 public IBuilder Append(HrbcField field, FieldCollection fieldCollection)
 {
     return(Append(field, builder => builder.Append(fieldCollection)));
 }
 public void Add(HrbcField key, FieldCollection value)
 {
     content.Add(key, value);
 }