console
var inputBox = document.querySelector('#inputbox'),
check = document.querySelector('#check');
inputBox.addEventListener('keyup',function(){
if (inputBox.value.length <=6) {
check.innerText = '密码长度要大于6'
} else{
var rank = fnCheck(inputBox.value);
if (rank >= 4) {
check.innerText = '强';
}else if(rank >1){
check.innerText = '中';
}else{
check.innerText = '弱';
}
}
})
function fnCheck(val){
var num = 0,
hasLowerCase = val.search(/[a-z]/),
hasUperCase = val.search(/[A-Z]/),
hasNum = val.search(/[0-9]/);
var others = val.split('').some(function(v){
var asc = v.charCodeAt();
return ((asc>32 && asc<48) || (asc>57 && asc<65) || (asc>90 && asc<97) || (asc>122 && asc<127));
});
if (hasLowerCase>-1) {
num++;
}
if(hasUperCase>-1){
num++;
}
if(hasNum>-1){
num++;
}
if (others) {
num = num+2;
}
return num;
}
<input type="password" placeholder='请输入密码' id='inputbox'/><br />
密码强度:<span id="check"></span>