<script language="javascript">
function CopyText(el){
    var selectedText = "";
    if(window.getSelection){
        selectedText = window.getSelection();
    }else if (document.getSelection){
        selectedText = document.getSelection();
    }else if (document.selection){
        selectedText = document.selection.createRange().text;
    } 
    if(selectedText != ""){
        selectedText = selectedText.toString();
        el.focus();
        el.value = selectedText;
        }else {
        alert("Select a text in the page and then press this button!");
    }
}
</script>
 
Select any part of this text to copy it...
<form name="frmCopyText">
<textarea name="txtSelect" rows="4" cols="45"></textarea><br>
<input onclick="CopyText(this.form.txtSelect)"
       type="button"
       value="Press to copy the highlighted text"
       name="btnCopy">
</form>

http://www.apphp.com/index.php?snippet=javascript-copy-selected-text

Sometimes you have some information on your page and your visitors might want to copy it. The easiest way is to provide a mechanism that allows them to simply click a button to do so. You have to paste this code into the head of your web page:

Copy Selected Text in JavaScript

javascript, text

JavaScript