Why this is not working in IE but working great in FF?

[Revos]

I got this code from this site and here it works GREAT in both FF and IE.
[code]
function surroundText(text1, text2, textarea)
{
// Can a text range be created?
if (typeof(textarea.caretPos) != "undefined" && textarea.createTextRange)
{
var caretPos = textarea.caretPos;
var temp_length = caretPos.text.length;

caretPos.text = caretPos.text.charAt(caretPos.text.length - 1) == ' ' ? text1 + caretPos.text + text2 + ' ' : text1 + caretPos.text + text2;

if (temp_length == 0)
{
caretPos.moveStart("character", -text2.length);
caretPos.moveEnd("character", -text2.length);
caretPos.select();
}
else
textarea.focus(caretPos);
}
// Mozilla text range wrap.
else if (typeof(textarea.selectionStart) != "undefined")
{
var begin = textarea.value.substr(0, textarea.selectionStart);
var selection = textarea.value.substr(textarea.selectionStart, textarea.selectionEnd - textarea.selectionStart);
var end = textarea.value.substr(textarea.selectionEnd);
var newCursorPos = textarea.selectionStart;
var scrollPos = textarea.scrollTop;

textarea.value = begin + text1 + selection + text2 + end;

if (textarea.setSelectionRange)
{
if (selection.length == 0)
textarea.setSelectionRange(newCursorPos + text1.length, newCursorPos + text1.length);
else
textarea.setSelectionRange(newCursorPos, newCursorPos + text1.length + selection.length + text2.length);
textarea.focus();
}
textarea.scrollTop = scrollPos;
}
// Just put them on the end, then.
else
{
textarea.value += text1 + text2;
textarea.focus(textarea.value.length - 1);
}
}
[/code]
I use it so:
[code]
<input type="button"
onClick="window.location.href='javascript:void(0)';
surroundText('[I]', '[/I]', document.FormPost.Post); return false;"
value=" I"
style="border-right-width:1px;
border-bottom-width:1px; border-top-width:1px;border-left-width:1px;
font-family:Arial; font-style:italic; font-size:12px" />
[/code]
Why it is not working it Internet Explorer?
In FireFox it is working GREAT!

[fenway]

Which part?

[Revos]

it is not going to this part:
[code]
if (typeof(textarea.caretPos) != "undefined" && textarea.createTextRange)
{
var caretPos = textarea.caretPos;
var temp_length = caretPos.text.length;

caretPos.text = caretPos.text.charAt(caretPos.text.length - 1) == ' ' ? text1 + caretPos.text + text2 + ' ' : text1 + caretPos.text + text2;

if (temp_length == 0)
{
caretPos.moveStart("character", -text2.length);
caretPos.moveEnd("character", -text2.length);
caretPos.select();
}
else
textarea.focus(caretPos);
}
[/code]
it is skiping this and going to the last ELSE part!

[fenway]

Test each piece of that if statement separately.

[Revos]

let me tell you what happens:
[code]
if (typeof(textarea.caretPos) != "undefined" && textarea.createTextRange)
{
var caretPos = textarea.caretPos;
var temp_length = caretPos.text.length;

caretPos.text = caretPos.text.charAt(caretPos.text.length - 1) == ' ' ? text1 + caretPos.text + text2 + ' ' : text1 + caretPos.text + text2;

if (temp_length == 0)
{
caretPos.moveStart("character", -text2.length);
caretPos.moveEnd("character", -text2.length);
caretPos.select();
}
else
textarea.focus(caretPos);
}
[/code]
the IF part suppost to check if it's IE but when I use IE it doesn't do the IF part and goes to the last ELSE part, why?!

[Revos]

ok let me change my question, what it wrong in this code in IE?
[code]
if (typeof(textarea.caretPos) != "undefined" && textarea.createTextRange)
{
var caretPos = textarea.caretPos;
var temp_length = caretPos.text.length;

caretPos.text = caretPos.text.charAt(caretPos.text.length - 1) == ' ' ? text1 + caretPos.text + text2 + ' ' : text1 + caretPos.text + text2;

if (temp_length == 0)
{
caretPos.moveStart("character", -text2.length);
caretPos.moveEnd("character", -text2.length);
caretPos.select();
}
else
textarea.focus(caretPos);
}
[/code]

[fenway]

So it does get into the this if block, or it doesn't?