// 注册字体 输入字体的路径(相对于index.html)
export function registerFallbackFont(serverPath) {
var xhr = new XMLHttpRequest()
xhr.open('GET', serverPath, true)
xhr.responseType = 'blob'
xhr.onload = function(e) {
if (this.status == 200) {
// get binary data as a response
var blob = this.response