实现文本域的maxlength

来源：互联网发布：沪港通每日交易数据编辑：程序博客网时间：2024/05/17 01:10

//onPropertyChange

function chkMaxLen(obj, e) {            var maxLen = 200;            if (getRangeById()) {                return true;            }            if (obj.value.length >= maxLen) {                if (e.keyCode == 46 || e.keyCode == 8 || (e.keyCode >= 33 && e.keyCode <= 40)) {                    return true;                } else {                    if (!e.ctrlKey)                        e.returnValue = "";                    return false;                }            }        }        function getRangeById() {            var o = document.selection.createRange();            if (o.text.length > 0) {                return true;            } else {                return false;            }        }        function clearSelect() {            var o = document.selection.createRange();            o.text = "";        }

onpaste="return false;"                            oncopy="return false;" oncut="return false;" onfocus="clearSelect();" onKeydown="chkMaxLen(this,event)" onblur="chkMaxLen(this,event)"