Remove tags from selected text in textarea

[eevan79]

I want to add button that remove tags (remove formating) from selected text in textarea.

Here is my code for adding BBCode tags between selected text:

 

function formatText(el,tagstart,tagend) {
      if (el.setSelectionRange) {
         el.value = el.value.substring(0,el.selectionStart) + tagstart + el.value.substring(el.selectionStart,el.selectionEnd) + tagend + el.value.substring(el.selectionEnd,el.value.length)
      }
      else {
      }
  }

Than I just add another function for tags:

 

function AddTag(tag) {
formatText(document.getElementById('textarea'),'['+tag+']','[/'+tag+']');
}

 

And add tag button will look like:

<button title="bold" onclick="AddTag('b');" type="button" style="background-image:url('img/editor/text_bold.gif');"></button>

This button will add [ b] and [ / b] between selected text in textarea.

 

I have tried this code but this remove all tags, not just for selected text:

function deleteTags(){
var tags=[
'\\[b\\]',
'\\[\/b\\]',
'\\[url\\]',
'\\[/url\\]',
'\\[u\\]',
'\\[\/u\\]'
]
var my = document.getElementById('mytextarea'), i=0, reg, t;
while(t=tags[i++]){
reg=new RegExp(t,'gi');
my.value = my.value.replace(reg,'');
}
}

 

How can I add another button to remove all tags ( [ b] , [ u ], [ quote ] etc...), but from selected text?