function wordcount(textobj,displayobj) {
 var word_count=textobj.value.length;
	//var word_count=getByteCount(textobj.value);
	displayobj.innerHTML = word_count + ' 字';
}

function commentwordcount(textobj,displayobj) {
 var word_count=textobj.value.length;
	displayobj.innerHTML = (100 - word_count) + ' 字剩下';
}

function checkIsSChinese(value) {
		for (var i = 0; i < value.length; ++i) {
				var c = value.charCodeAt(i);
				if (c < 256 || (c >= 0x80 && c <= 0xff)) {
						return false;
				}
		}
		return true;
}
    
function getByteCount(value) {
		var count = 0;
		for ( var i = 0; i < value.length; ++i ) {
				var sub = value.substring(i, i + 1);
				if( checkIsSChinese(sub) ){
						count += 2;
				} 
				else {
						count += 1;
				}
		}
		return count;
}

function check() {
		alert(getByteCount(document.f.txt.value) + " 字")
}