vue使用print打印时，会多出空白页，这多半是外边距导致的，将打印的dom对象的margin 设置为0，即可解决
<style media="printContent">
@page {
size: auto; /* auto is the initial value /
margin: 3mm; / this affects the margin in the printer settings */
}
html {
background-color: #ffffff;
margin: 0px; /* this affects the margin on the html before sending to printer */
}
body {
border: solid 1px rgba(255,255,255,0);
/* margin: 10mm 15mm 10mm 15mm; margin you want for the content */
}
</style>
