!DOCTYPE html html head meta charsetUTF-8 title/title script var opwd1null; var opwd2null; window.onloadfunction(){ //获取密码1的对象 opwd1 document.getElementById(pwd1); //获取密码2的对象 opwd2 document.getElementById(pwd2); } function show(){ if(opwd1.value){ alert(密码不能为空); return; } if(opwd1.value!opwd2.value){ alert(两次输入密码不一致); return; }else{ alert(密码一致); } } /script /head body 密码1:input typepassword name idpwd1 /br / 密码2:input typepassword name idpwd2 /br / input typebutton value验证密码 onclickshow()/ /body /html