Is there any way to make a method with more than one instance?

Question

private void Extractions(string htmlFileName, int offLineFileNumber, bool onlineOffline)
        {
            if (onlineOffline == false)
            {
                OffLineDownload.offhtmlfiles();
                page = OffLineDownload.OffLineFiles[offLineFileNumber];
                byte[] bytes1 = File.ReadAllBytes(page);
                page = Encoding.GetEncoding(1255).GetString(bytes1);
                TextExtractor.GetDateTimeList(page);
                StreamWriter w = new StreamWriter(@"C:\Temp\" + htmlFileName);//@"d:\rotterhtml\rotterscoops.html");
                w.Write(page);
                w.Close();
                extractlinks.Links(@"C:\Temp\" + htmlFileName);
                TextExtractor.ExtractText(@"C:\Temp\" + htmlFileName, newText);
            }
            else
            {
                client.Encoding = System.Text.Encoding.GetEncoding(1255);
                page = client.DownloadString("http://rotter.net/scoopscache.html");
                TextExtractor.GetDateTimeList(page);
                StreamWriter w = new StreamWriter(@"d:\rotterhtml\rotterscoops.html");
                w.Write(page);
                w.Close();
                extractlinks.Links(@"d:\rotterhtml\rotterscoops.html");
                TextExtractor.ExtractText(@"d:\rotterhtml\rotterscoops.html", newText);
            }
        }

If the user calls the method I want him to have two options to call it with all 3 variables:

string htmlFileName, int offLineFileNumber, bool onlineOffline

Or to call it without the variables and if it's () so it will be automatic true.

There are various ways to achieve this. Overloaded methods or optional parameters. In the original version of C#, optional parameters were not supported and some think that overloaded methods are better, due to a clearer "contract" between the caller and the class. — Marius George, Jun 27 '14 at 15:43

Mukesh Modhvadiya · Answer 1 · 2014-06-27T15:57:45.753

2

You can use optional arguments to achieve what you want :

private void Extractions(string htmlFileName="", int offLineFileNumber=0, bool onlineOffline=true)
{
    // implementation
}

Then you can call your method with required parameters, something like :

Extractions("myfile.txt", 1, true);  // or
Extractions("myfile.txt", 1)

edited Jun 27 '14 at 15:57

answered Jun 27 '14 at 15:37

Mukesh Modhvadiya

2,178
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32

A little more explanation: http://msdn.microsoft.com/en-us/library/dd264739.aspx – Dennis_E Jun 27 '14 at 15:38

score 1 · Accepted Answer · answered Jun 27 '14 at 15:36

You can "overload" the method. Have the same name with multiple parameter signatures.

private void Extractions()
{

}

Since your method is a "void", I don't know what you mean by " if it's () so it will be automatic true."

Unless what you meant was:

private void Extractions(string htmlFileName, int offLineFileNumber)
{
     Extractions(htmlFileName, offLineFileNumber, true);
}

Of course you could also just make the offLine paremeter optional and give it a default of true.

private void Extractions(string htmlFileName, int offLineFileNumber, bool onlineOffLine = true)
{
     ....
}

A method without parameters is a property. You could create a property called Extractions that is a boolean, that always returns false. But that would be confusing to me. Methods and Properties are different in fact and in meaning. — Bill Gregg, Jun 27 '14 at 15:41

score 0 · Answer 3 · answered Jun 27 '14 at 15:38

Yes, it's called method overloading.

Just define your method multiple times, with different parameters

private void Extractions(string htmlFileName, int offLineFileNumber, bool onlineOffline)
{
  //All your logic here
}

Overloaded method:

private void Extractions(string htmlFileName, int offLineFileNumber)
{
// Call the main method, passing true
Extractions(htmlFileName, offLineFileNumber, true);
}

See here: http://csharpindepth.com/Articles/General/Overloading.aspx

Is there any way to make a method with more than one instance?

3 Answers3