Transform Parameters refactoring
ReSharper_TransformParameters
This refactoring helps you quickly change method signature by transforming parameters — e.g. get rid of out parameters, wrap parameters in a tuple or in a new class, etc. — and automatically update all usages of the method in your solution.
The refactoring lets you perform the following transformations:
- Create a new class with public fields or auto-properties for types corresponding to the selected parameters, and use the newly created class instead of parameters.
- Replace parameters with a tuple object.
- For a method returning
void, transform a selectedoutparameter to method return. - For a method returning
void, wrap multiple selectedoutparameters to a tuple object and use it as method return. - For a method returning
void, create a new class with public fields or auto-properties for types corresponding to the selectedoutparameters, and use the newly created class as method return. - For non-void methods with
outparameters, combineoutparameters with return type in a tuple object or in a newly created class.
The example below demonstrates a mix of transformations - we replace out parameter with method return, and we wrap two other parameters with a new class:
| Before refactoring | After refactoring |
|---|---|
class TestClass
{
public void DrawCircle(Point ctr,
float rad, out bool res)
{
// draw...
res = true;
}
} | class TestClass
{
public bool DrawCircle(Circle circle)
{
// draw... .
var res = true;
return res;
}
}
internal class Circle
{
public Circle(Point ctr, float rad)
{
Ctr = ctr;
Rad = rad;
}
public Point Ctr { get; private set; }
public float Rad { get; private set; }
} |
To transform method parameters
- Place the caret at the declaration or a usage of method in the editor, or select the method in the File Structure window. Or, alternatively set the caret at any of method parameters.
- Do one of the following:
- Press Ctrl+Shift+R and then choose Transform Parameters
- Right-click and choose Refactor | Transform Parameters in the context menu.
- Choose in the main menu.
- Select parameters you want to transform.
- Depending on selected in/out parameters, ReSharper enables Method receives and/or Method returns selectors. Use these selectors to choose how in/out parameters should be transformed. If you choose to create a new class for parameters, you will be able to specify its name in a text box to the right of it.
- To apply the refactoring, click Next.
- If no conflicts are found, ReSharper performs the refactoring immediately. Otherwise, it prompts you to resolve conflicts.
This feature is supported in the following languages and technologies:
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The instructions and examples given here address the use of the feature in C#. For details specific to other languages, see corresponding topics in the ReSharper by Language section.