js 打印

 /* 打印 方法 */
    function doPrint() {
        console.log('doPrint')
        bdhtml = window.document.body.innerHTML;
        sprnstr = "<!--startprint-->";
        eprnstr = "<!--endprint-->";
        console.log(sprnstr);
        prnhtml = bdhtml.substr(bdhtml.indexOf(sprnstr) + 17);
        prnhtml = prnhtml.substring(0, prnhtml.indexOf(eprnstr));
        if (!prnhtml) {
            mu.showLoading({
                title: '暂无可打印内容'
            })
            return;
        }

        window.document.body.innerHTML = prnhtml;
        printStart();
        window.print();
        window.document.body.innerHTML = bdhtml;
        printEnd();
        // 刷新页面
    }
    function printStart() {
        var arr = getClass(document, "opy")
        arr.forEach((item, index) => {
            item.classList.add('opy-0')
        })
        var arr1 = getClass(document, "inpu")
        arr1.forEach((item, index) => {
            item.classList.remove('bt')
        })
    }

    function printEnd() {
        var arr = getClass(document, "opy")
        arr.forEach((item, index) => {
            item.classList.remove('opy-0')
        })
        var arr1 = getClass(document, "inpu")
        arr1.forEach((item, index) => {
            item.classList.add('bt')
        })
    }
    function getClass(oParent, classname) {
        var oChild = oParent.getElementsByTagName('*');
        var arr = [];

        for (var i = 0, len = oChild.length; i < len; i++) {
            if (oChild[i].className.indexOf(classname) >= 0) {
                arr.push(oChild[i]);
            }
        }
        return arr;
    }