一直用JQuery，JavaScript都有些忘记了，今天又拾起来了。。。

<script LANGUAGE=javascript RUNAT=Server>function isEmail(strEmail) {/***检测邮箱**/var tdEmailTip = document.getElementById("email_td");var td_email_tip = document.getElementById("email_tip");var textNode1 = document.createTextNode("请输入邮箱地址");var td_email_tip = document.getElementById("email_tip");var textNode2 = document.createTextNode("请输入正确的邮箱地址");var img = document.createElement("img");img.src="img/zc_dh.png";img.id="img";var op = document.createElement("p")op.id ="email_tip";if(document.getElementById("email_chk").value==""&&!document.getElementById("email_tip").hasChildNodes()){td_email_tip.appendChild(textNode1);document.getElementById("email_chk").focus();}if(document.getElementById("email_chk").value!=""){if(document.getElementById("email_td").hasChildNodes()){   tdEmailTip.removeChild(td_email_tip);}if (strEmail.search(/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/) != -1){if(document.getElementById("email_td").hasChildNodes()){tdEmailTip.removeChild(td_email_tip);}op.appendChild(img);tdEmailTip.appendChild(op);}else{if(document.getElementById("email_td").hasChildNodes()){tdEmailTip.removeChild(td_email_tip);}op.appendChild(textNode2);tdEmailTip.appendChild(op);}}}/***检验昵称**/function isNikName(nickname){var nick_td = document.getElementById("name_td");var nick_p = document.getElementById("pName");var nickname=document.createElement("p");nickname.id="pName";var textname = document.createTextNode("请输入昵称");if(document.getElementById("nikname").value==""){if(!document.getElementById("name_td").hasChildNodes()){nickname.appendChild(textname);nick_td.appendChild(nickname);}}else{if(document.getElementById("name_td").hasChildNodes()){nick_td.removeChild(nick_p);}}}/***检验密码**/function PasswordStrength(passwordID,strengthID){this.init(strengthID);var _this = this;document.getElementById(passwordID).onkeyup = function(){_this.checkStrength(this.value);}};PasswordStrength.prototype.init = function(strengthID){var id = document.getElementById(strengthID);var div = document.createElement('div');var strong = document.createElement('strong');this.oStrength = id.appendChild(div);this.oStrengthTxt = id.parentNode.appendChild(strong);};PasswordStrength.prototype.checkStrength = function (val){var aLvTxt = ['','低','中','高'];var lv = 0;if(val.match(/[a-z]/g)){lv++;}if(val.match(/[0-9]/g)){lv++;}if(val.match(/(.[^a-z0-9])/g)){lv++;}if(val.length < 6){lv=0;}if(lv > 3){lv=3;}this.oStrength.className = 'strengthLv' + lv;this.oStrengthTxt.innerHTML = aLvTxt[lv];};/***进行其他项输入***/function chk_pwd(pwd){document.getElementById("pwd_strength").style.display="none";}/***密码强度框显示**/function pwd_display(){document.getElementById("pwd_strength").style.display="block";}/***确认密码**/function chk_repwd(){if(document.getElementById("pass").value==""){//alert("s输入");var pwd_tip = document.getElementById("re_pwdchk");var tippwd = document.createElement("p");tippwd.id = "pwd_re";var pp = document.getElementById("pwd_re");var textNode = document.createTextNode("请输入密码");if(!document.getElementById("re_pwdchk").hasChildNodes()){tippwd.appendChild(textNode);pwd_tip.appendChild(tippwd);}}}
</script>