Why does my ajax request strip out a '\' backslash character?

Question

I'm calling a rest endpoint with ajax that is like this. It takes two params user and permission

$.ajax({
    type: 'GET',
    cache: false,
    url: "/app/Rest/4.0/UserManagement/AddPermissionToUser",
    data: {
        username: encodeURI(user),
        permissionName: encodeURI(permission)
    },
    success: function (msg) {
        //do stuff
    }
});

In the javascript, let's say may user is something like domain\user1, the ajax request strips out the backslash character. Originially I didn't have the encodeUri()'s in there

One more curious thing is that if I manually stick this url in my browser encoding it like this domain%5Cuser1 it works as expected. I am in IE 11, is the browser stripping this off, or is it a problem with jQuery? Any ideas?

Answer 1

The \ may be seen as being used to escape special characters server-side.

Try passing a string like domain\\user1, to see if it comes through as a single slash.

It's possible there is a better solution, but we would need to see what you're doing with the string in your server-side code.