封装本地文件路径

var file = document.getElementById('mapFile').files[0];
var url = getObjectURL(file)；

// 封装本地上传文件路径
function getObjectURL(file) {
var url = null;
if (window.createObjcectURL != undefined) {
url = window.createOjcectURL(file);
}else if (window.URL != undefined) {
url = window.URL.createObjectURL(file);
} else if (window.webkitURL != undefined) {
url = window.webkitURL.createObjectURL(file);
}
return url;
}