随笔开发中笔记

微信小程序中视频的的控件样式 video   controls=“false” 是无效的  

解决：

controls="{{false}}"

弹出的浏览器窗口居中显示

function Fun(height,width){window.open ('src', '_blank', 'height='+height+', width='+width+',top='+(screen.height-height)/2+',left='+(screen.width-width)/2+' ,toolbar=no,menubar=no, scrollbars=no, resizable=no,location=n o, status=no'); }

移动端布局 rem

 //移动端rem适配
function getRem(pwidth,prem){
    var html = document.getElementsByTagName("html")[0];
    var oWidth = document.body.clientWidth || document.documentElement.clientWidth;
    console.log(oWidth);
    html.style.fontSize = oWidth/pwidth*prem + "px";
}
getRem(750,100);//1rem 等于100px

购物车加减效果

 <button>+</button>
    <input type="text" value="1">
    <button>-</button>
    <script>
    var btn = document.getElementsByTagName('button');
    console.log(btn);
    var Input = document.getElementsByTagName('input')[0];
    btn[0].onclick = function() {
        Input.value = (Input.value++) === 999 ? 999 : Input.value;
    };
    btn[1].onclick = function() {
        Input.value = (Input.value--) == 0 ? 0 : Input.value;
    }
    </script>