CODEWITHSUNDEEP
c#refactoring
Steve B
Steve B

Reputation: 37690

Refactor C# automatic properties to fields and getter/setter property?

I have a bunch of business class with autoproperties :

public class A {

    public int Id { get; set; }
    public string Title { get; set;}

}

Because the application evolves, there is a new requirement to enable tracking the changes of the properties, in order to send to the backing store only changed data.

In order to reach this goal, I have to convert ALL properties to field + property like this :

public class A {

    private int m_Id;
    public int Id {
        get { return m_Id; }
        set {
            if(m_Id != value){
                SetChanged("Id");
                m_Id = value;
            }
        }
    }
    private string m_Title;
    public string Title 
    { 
        get { return m_Title; }
        set {
            if(m_Title != value){
                SetChanged("Title");
                m_Title = value;
            }
        }
    }

    protecte void SetChanged(string propertyName) { 
        // Not important here
    }
}

Is there a way to quickly refactor my code to avoid having to manually change the properties ?

Upvotes: 5

Views: 3397

Answers (4)

Dr. Andrew Burnett-Thompson
Dr. Andrew Burnett-Thompson

Reputation: 21541

There's no way in the IDE to do this, but if you need to replace all X properties, I would write a short console application to do it.

The process would be:

  • Iterate over all files in directory matching *.cs
  • Foreach file, regex find and replace old property for new property syntax

Using regex to match is very powerful. Regex can be used in VS2010 to do a find/replace operation. If you try finding this (with regex enabled)

{(public|private|internal|protected)}:b{[a-zA-Z0-9]+}
:b{[a-zA-Z0-9]+}:b\{ get; set; \}

It will match properties like this

public Type Foo { get; set; }

In your console application find all lines of code that match the above, then start splitting them up into Modifier, Type, Property Name and finally replacing the whole block with something like this

// PS: this is pseudocode ;-) or could be your new property template
private [Type] m_[PropertyName].ToPascaleCase
public [Type] PropertyName
{
    get { return m_[PropertyName].ToPascaleCase; }
    set
    {
        if(m_[PropertyName].ToPascaleCase != value){
            SetChanged([PropertyName]);
            m_[PropertyName].ToPascaleCase = value;
        }
    }
}

Finally I would advocate taking a backup of your code or running this test offline and testing before checking in!!

Upvotes: 3

gunr2171
gunr2171

Reputation: 17578

There is probably no direct way of doing this with refraction. If this was my problem. I would make code to generate this:

public string MakePropertyBigger(string varName, string propName, string dataType)
{
    string output = "";
    output += string.Format("private {0} {1};", dataType, varName) + Environment.NewLine;
    output += string.Format("public {0} {1}", dataType, propName) + Environment.NewLine;
    output += "{" + Environment.NewLine;
    output += string.Format("get { return {0}; }", varName) + Environment.NewLine;
    output += string.Format("set { if({0} != value){ SetChanged(\"{1}\");", varName, propName) + Environment.NewLine;
    output += string.Format("{0} = value; }", varName) + Environment.NewLine;
    output + "}" + Environment.NewLine + "}";

Now just plug this in and chug it out.

Upvotes: 0

Nick Babcock
Nick Babcock

Reputation: 6141

You can always just create a generic method that will do the assignment and call SetChange

void SetChangeIfNeeded<T>(ref T field, T value, string propertyName)
{
    if (!EqualityComparer<T>.Default.Equals(field, value))
    {
        field = value;
        SetChanged(property);
    }
}

You would still need to have a private back field. Your class would look something like:

public class A {  

    private int m_id
    public int Id 
    { 
        get { return m_id };
        set { SetChangeIfNeeded<int>(ref m_id, value, "Id"); }
    }  
}

Upvotes: 1

dwonisch
dwonisch

Reputation: 5785

ReSharper can do this, but wouldn't modify setter.

public string Title {
    get { return m_title; }
    set { m_title = value; }
}

Upvotes: 0

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