密码可见性切换（显示和隐藏）

示例：

HTML代码：

    <div class="password-wrap">
        <div class="password-input">
            <input type="password" name="key" value='www.css88.com' class="bui-input" autocomplete="off" />
        </div>
        <i class="bt-showpwd off"></i>
    </div>
    

CSS代码：

@font-face {
  font-family: 'iconfont';  /* project id 674189 */
  src: url('//at.alicdn.com/t/font_674189_dvawifegwrj.eot');
  src: url('//at.alicdn.com/t/font_674189_dvawifegwrj.eot?#iefix') format('embedded-opentype'),
  url('//at.alicdn.com/t/font_674189_dvawifegwrj.woff') format('woff'),
  url('//at.alicdn.com/t/font_674189_dvawifegwrj.ttf') format('truetype'),
  url('//at.alicdn.com/t/font_674189_dvawifegwrj.svg#iconfont') format('svg');
}
.iconfont {
  display: inline-block;
  font-family: 'iconfont';
  font-style: normal;
  text-rendering: auto;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
          -webkit-transform: translate(0, 0);
              -ms-transform: translate(0, 0);
                  transform: translate(0, 0);
  -webkit-text-stroke-width: 0.2px;
}

.bui-input {
    box-sizing: border-box;
    height: 40px;
    padding: 8px 10px;
    line-height: 24px;
    border: 1px solid #DDDDDD;
    color: #5F5F5F;
    font-size: 14px;
    vertical-align: middle;
    border-radius: 4px;
    width: 330px;
}
.bui-input:hover{
    border: 1px #659aea solid;
}
.bui-input:focus {
    outline: none;
    border: 1px solid #4F9FE9;
    box-shadow: 0 0 3px 0 #2171BB;
    color: #595959;
}
.password-wrap { position: relative; width: 330px; }
.password-wrap .bt-showpwd { color: #999999; position: absolute; top: 8px; right: 10px; line-height: 24px; width: 24px; height: 24px;    text-align: center; cursor: pointer; }
.password-wrap .bt-showpwd.off::before { content: "\e60a"; font-family: "iconfont"; font-size: 18px; }
.password-wrap .bt-showpwd.on::before { content: "\e60b"; font-family: "iconfont"; font-size: 18px; }

JavaScript代码：

$(".bt-showpwd").on("click",  function (e) {
    e.preventDefault();
    var $this = $(this);
    var $password = $this.closest(".password-wrap");
    var $input = $password.find('input');
    var $inputWrap = $password.find('.password-input');
    var newinput = '', inputHTML = $inputWrap.html(), inputValue = $input.val();
    if ($input.attr('type') === 'password') {
        newinput = inputHTML.replace(/type\s*=\s*('|")?password('|")?/ig, 'type="text"');
        $inputWrap.html(newinput).find('input')[0].value = inputValue;
        $this.removeClass("off").addClass("on");
    } else {
        newinput = inputHTML.replace(/type\s*=\s*('|")?text('|")?/ig, 'type="password"');
        $inputWrap.html(newinput).find('input')[0].value = inputValue;
        $this.removeClass("on").addClass("off");
    }
});