跳轉(zhuǎn)路由前做判斷美澳，決定是否跳轉(zhuǎn)
this.context.router.setRouteLeaveHook(
this.props.route,
()=> {
if (this.state.uploadFinish === false) {
return '上傳未完成杜跷，確認退出?';
}
})
聲明類型：
Uploading.contextTypes = {
router: React.PropTypes.object
}
