express设置允许跨域请求
//设置跨域访问
app.all("*", function (req, res, next) {
//设置允许跨域的域名,*代表允许任意域名跨域
res.header("Access-Control-Allow-Origin", req.headers.origin || '*');
// //允许的header类型
res.header("Access-Control-Allow-Headers", "Content-Type, Authorization, X-Requested-With");
// //跨域允许的请求方式
res.header("Access-Control-Allow-Methods", "PUT,POST,GET,DELETE,OPTIONS");
// 可以带cookies
res.header("Access-Control-Allow-Credentials", true);
if (req.method == 'OPTIONS') {
res.sendStatus(200);
} else {
next();
}
})