<!DOCTYPE html>
<html>
<head>
<Meta HTTP-equiv = "the Type-the Content" Content = "text / HTML; charset = UTF-. 8" />
<title> based on the input text box highly adaptive </ title>
<style type = "text / CSS ">
H2 {
text-align = left: Center;
margin: Auto 50px;
}
#textarea {
display: block;
margin: 0 auto;
overflow: hidden;
width: 550px;
font-size: 14px;
height: 18px;
line-height: 24px;
padding: 2px;
}
TextArea {
Outline: 0 none;
border-Color: RGBA (82, 168, 236, 0.8);
Box-Shadow: the inset from 0 1px 3px RGBA (0, 0, 0, 0.1), 0 0 8px RGBA (82, 168, 236, 0.6);
}
</ style>
<Script>
/ ***
* highly adaptive textbox based on the input
* @param {HTMLElement} input element
* @param {Number} provided from the input frame holding the cursor ( default 0)
* @param {set} Number The maximum height (optional)
* /
var autoTextarea = function (elem, Extra, the maxHeight) {
Extra Extra || = 0;
var = !! isFirefox document.getBoxObjectFor || 'mozInnerScreenX' window in,
isOpera = !! window.opera && !! window.opera.toString (). indexOf ( 'Opera'),
addEvent = function (of the type, callback) {
elem.addEventListener?
elem.addEventListener(type, callback, false) :
elem.attachEvent('on' + type, callback);
},
getStyle = elem.currentStyle ? function(name) {
var val = elem.currentStyle[name];
if (name === 'height' && val.search(/px/i) !== 1) {
var rect = elem.getBoundingClientRect();
return rect.bottom - rect.top -
parseFloat(getStyle('paddingTop')) -
parseFloat(getStyle('paddingBottom')) + 'px';
};
return val;
} : function(name) {
return getComputedStyle(elem, null)[name];
},
minHeight = parseFloat(getStyle('height'));
elem.style.resize = 'none';
var change = function() {
var scrollTop, height,
padding = 0,
style = elem.style;
if (elem._length === elem.value.length) return;
elem._length = elem.value.length;
if (!isFirefox && !isOpera) {
padding = parseInt(getStyle('paddingTop')) + parseInt(getStyle('paddingBottom'));
};
scrollTop = document.body.scrollTop || document.documentElement.scrollTop;
elem.style.height = minHeight + 'px';
if (elem.scrollHeight > minHeight) {
if (maxHeight && elem.scrollHeight > maxHeight) {
height = maxHeight - padding;
style.overflowY = 'auto';
} else {
height = elem.scrollHeight - padding;
style.overflowY = 'hidden';
};
style.height = height + extra + 'px';
scrollTop += parseInt(style.height) - elem.currHeight;
document.body.scrollTop = scrollTop;
document.documentElement.scrollTop = scrollTop;
elem.currHeight = parseInt(style.height);
};
};
addEvent('propertychange', change);
addEvent('input', change);
addEvent('focus', change);
change();
};
</script>
</head>
<body>
<H2> based on the input text box highly adaptive </ H2>
<TextArea ID = "TextArea" placeholder = "reply"> </ TextArea>
<Script>
var text = document.getElementById ( "TextArea") ;
autoTextarea (text); // call
</ Script>
</ body>
</html>
