如何使用JavaScript永久修改单独文件上的JSON对象？

Question

I've been trying for a while to modify my json formatted database (db.txt) which lies on a server with JS, but can't get the file to change. It loads into my JS script perfectly with ajax GET, but I can't make it change.

Here is the code I'm trying and failing with:

$.ajax
({
    type: "POST",
    url: 'db.txt',
    dataType: 'json',
    async: false,
    data: {"test": "test23123"},
    success: function () {
    alert("posting success!!!!"); 
    }
})

Here is the db.txt:

{
"Hoegaarden, Wit-Blanche": {"namn" : "Hoegaarden, Wit-Blanche", "pris" : 20, "volym" :

 500, "uppdaterad" : "2013-06-27"},
    "Jaegermeister": {"namn" : "Jaegermeister", "pris" : 150, "volym" : 700, "uppdaterad" : "2013-06-27"},
    "Miller": {"namn" : "Miller", "pris" : 20, "volym" : 500, "uppdaterad" : "2013-06-27"}
}

It gives me the success alert when I run it, but nothing happens to the txt.db. Can I modify it to work? If not, what method could I use instead?

Thanks

Answer 1

JavaScript cannot modify files on the server. You'll need a server-side language (like PHP) to do it.

Some Points:

• What's the difference between server-side and client-side programming?
• A file that contains JSON should end with the .json extension.
• dataType is the type of data you're expecting. contentType is the type of data you're transferring (that's what you want).

Answer 2

You cannot modify the file that resides on the server that way. JavaScript has no access to the file on the server. Instead, you need to expose a URL through a server-side app that does this for you. You can do this with something like PHP, Java, or Node.js.