C#

DialogResult result = MessageBox.Show("do something?", "title here", MessageBoxButtons.YesNo);
if(result == DialogResult.Yes)
{
   // He clicked yes.
}
else 
{ 
   // he clicked no 
}

if( MessageBox.Show(Handle, msg, caption, MessageBoxButtons.RetryCancel, MessageBoxIcon.Question) == DialogResult.Retry)<br />
{<br />
    //Do something...<br />
}

DialogResult p = MessageBox.Show(Handle, msg, caption, MessageBoxButtons.RetryCancel, MessageBoxIcon.Question);<br />
if( p == DialogResult.Retry )<br />
{<br />
    //Do something...<br />
}

using System;<br />
//All namespace to attach<br />
<br />
namespace demo<br />
{<br />
    public class demo<br />
    {<br />
        public demo()<br />
        {<br />
            //this is the constructor but if the app is console application you need de main method<br />
        }<br />
<br />
        public Main()<br />
        {<br />
            this.demo();<br />
        }<br />
<br />
        private int Occurance(string Input, string Find) <br />
        { <br />
            System.Text.RegularExpressions.Regex rx = new System.Text.RegularExpressions.Regex(Find); // to display them do this <br />
            System.Text.RegularExpressions.Match mt = rx.Match(Input); <br />
            while (mt.Success) <br />
            { <br />
                System.Console.WriteLine("Found >>" + Find + "<< at position " + mt.Index.ToString()); <br />
                mt = mt.NextMatch(); <br />
            }<br />
<br />
            // end display <br />
            return rx.Matches(Input).Count; <br />
        } <br />
<br />
        private DateTime getDate(int day, int month, int year) <br />
        { <br />
            return new DateTime(year, month, day); <br />
        } <br />
<br />
        private void compareDates(DateTime a, DateTime b) <br />
        { <br />
            if (a > b) <br />
            {<br />
                Console.WriteLine(a.ToShortDateString() + " > " + b.ToShortDateString()); <br />
            }<br />
            else if (a == b) <br />
            {<br />
                Console.WriteLine(a.ToShortDateString() + " = " + b.ToShortDateString()); <br />
            }<br />
            else <br />
            {<br />
                Console.WriteLine(a.ToShortDateString() + " < " + b.ToShortDateString()); <br />
            }<br />
        } <br />
<br />
        ~demo()<br />
        {<br />
            //destructor<br />
        }<br />
<br />
    }<br />
}

SaveFileDialog dlg = new SaveFileDialog();
dlg.Filter = "Text Files|*.txt|Comma Seperated Files|*.csv|All Files|*.*";
dlg.InitialDirectory = @"C:\";
if (dlg.ShowDialog() == DialogResult.OK)
{
   using (System.IO.StreamWriter writer = new System.IO.StreamWriter(dlg.FileName))
   {
      writer.Write(txtContent.Text);
      writer.Flush();
   }
}