EJS not displaying value if only single item passed - html

Question

well while passing value from app.js file to checkout.ejs file, if I am checking multiple checkboxes, all the images associated gets displayed in checkout. ejs page, but if I press only a single checkbox to retrieve single image, it doesn't happen.
here is my app.js
app.post("/data", uploads, function (req, res) {
User.findById(req.user.id, function (err, foundUser) {
if (err) {
console.log(err);
} else {
if (foundUser) {
res.render("checkout",{SIMG:req.body.checkbox});
}
}
});
});
and here is my checkout.ejs
<% for(var i=0; i<SIMG.length; i++){ %>
<p> <img src="./uploads/<%=SIMG[i]%>" alt="image" width="300"></p>
<% } %>
</body>
</html>
In app.js, req.body.checkbox retrieves the image name of all the images selected from other pages, that I want to retrieve in the checkout page.
working fine if selected images are more than one, but for a single image
<img src="./uploads/<%=SIMG[i]%>" alt="image" width="300">
line in checkout.ejs runs continuously without displaying an image.

Answer 1

I guess you are getting array when you selecting multiple checkboxes but when you select one checkbox it will just give value, that's why it is not working. If you get single value, just convert into an array as well, as in below code
app.post("/data", uploads, function (req, res) {
User.findById(req.user.id, function (err, foundUser) {
if (err) {
console.log(err);
} else {
if (foundUser) {
// you can put more validation if you want, for empty or any other syntax
if (Array.isArray(req.body.checkbox)) {
res.render("checkout",{SIMG: req.body.checkbox});
} else {
res.render("checkout",{SIMG: [req.body.checkbox]});
}
}
}
});
});