copy text to clipboard

if the user want to copy some content ,he have to select some content then right click ,then click copy.if u want in ur appplication that there will be a control onclick of which the content of controls for example textbox will copy to click board,then call a javascript function onclick that button

< input type="button" value="copy" onclick="CopyToClipboard()
;">

function CopyToClipboard()
   {
     var textboxVal = document.getElementById("txtCopy").value; //txtText id of a textbox
      if( window.clipboardData && clipboardData.setData )
      {
         clipboardData.setData("Text", textboxVal);
      }
      else
      {
         alert("works only in IE4+");
      }
   }