如何让多行文本框中，选中文本的两端分别加上[b]和[/b]

Question

<script>
var selecting=false;
function test(obj) {
      selecting=true;
}
function mouseup(obj) {
     if(selecting){
            document.selection.createRange().text=[
                      "",
                      document.selection.createRange().text,
                      ""].join("");
            selecting=false;
     }
}
</script>
<input type="text" onselect="test(this)" onmouseup="mouseup(this)" value="select Me!"/>

Answer 1

<script> 
var str="3284234";
var re=/([\s\S]*)/;
alert(str.replace(re,"$1"))
</script>

Answer 2

文本框还应该加上 onMouseDown="selecting=false;"

Answer 3

自己觉得，文本框还应该加上： onMouseDown="selecting=false;"