Looks up and retrieves the Revit command id with the given id string. 
   Namespace:   Autodesk.Revit.UI  
  Assembly:   RevitAPIUI  (in RevitAPIUI.dll) Version: 2015.0.0.0 (2015.0.0.0) 
  Since:  2014 
Syntax
| C# | 
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| Visual Basic | 
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| Visual C++ | 
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Parameters
- postableCommand
 -  Type:  Autodesk.Revit.UI PostableCommand  
The postable command. 
Return Value
The Revit command id. Returning a null reference ( Nothing in Visual Basic) if a command with the given name was not found.Exceptions
| Exception | Condition | 
|---|---|
| Autodesk.Revit.Exceptions ArgumentNullException | Thrown when name is a null reference ( Nothing in Visual Basic) . |