Tips: try your best to use  Parameter(BuiltInParameter) when get parameter from element.

Revit as a parametric product, we will frequently use element parameters (retrieve, modify) to achieve our own goals.

There are several ways to get Parameter from an element:
Parameter(BuiltInParameter)
Parameter(Definition)
Parameter(Guid)
Parameter(String)

All almost similar except the last one which has the least performance because it will iterate all parameters in this element until find the parameter with the specified name. However, in most cases BuiltInParameter is more meaningful for us and easy to get, so it’s better for us to use BuiltInParameter to get parameter. In addition, use this can avoid localization problem, so you don’t need to write different code for different languages.

If you do need to use string to retrieve parameter, go ahead. But keep in mind that there is another property ParametersMap. If you want to search several parameters from one element (all use string as keyword), get this map first and use the map to get parameter would be faster.

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