Question

I want to compare 2 lines, but the one line is in a random sequence. I use text boxes, like this:

Textbox1:
friends
pals
elephant

Textbox2:
aspl

Now when I hit a button I want Textbox3 to show the following:

Textbox3:
pals

What I got so far:

            Textbox3.Clear();
            string[] lines1 = Textbox2.Lines;
            foreach (string line1 in lines1)
            {
                string[] lines = Textbox1.Lines;
                foreach (string line in lines)
                {
                    if (line.Contains(line1))
                    {

                        Textbox3.Text += line;
                        Textbox3.Text += "\r\n";
                    }
                }

             }

But this will only copy the line to Textbox3 if the line in Textbox1 and Textbox2 is totally identical, not just if the characters is identical.

So my question is: How do I do that?

Answer 1

Simply sort the strings and compare the results assuming they are equal length and not null this works:

    private static bool IsPermutation(string one, string two)
    {
        var oneSorted = String.Join("", one.OrderBy(c => c).Select(x => x.ToString()).ToArray());
        var twoSorted = String.Join("", two.OrderBy(c => c).Select(x => x.ToString()).ToArray());

        return oneSorted == twoSorted;
    }

EDIT: To answer the comment. Add that method to your class and replace the code inside your foreach with

if (line.Length == line1.Length && IsPermutation(line, line1)) 
{
   Textbox3.Text += line;
   Textbox3.Text += "\r\n";                    
}