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c# - How to access random item in list?

I have an ArrayList, and I need to be able to click a button and then randomly pick out a string from that list and display it in a messagebox.

How would I go about doing this?

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  1. Create an instance of Random class somewhere. Note that it's pretty important not to create a new instance each time you need a random number. You should reuse the old instance to achieve uniformity in the generated numbers. You can have a static field somewhere (be careful about thread safety issues):

    static Random rnd = new Random();
    
  2. Ask the Random instance to give you a random number with the maximum of the number of items in the ArrayList:

    int r = rnd.Next(list.Count);
    
  3. Display the string:

    MessageBox.Show((string)list[r]);
    

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