code: public DOField getFieldByName(String fieldName) {
  		int idx = this.getIndexOfField(fieldName);
  		if (idx != -1)
  			return this.getFieldByIndex(idx);
  		return null;
  	}
docs: Answer the field with the given name.
  <br/>Answer null if a field with the given name does not exist.
  @param fieldName
  @return