Question

as you know we can get post field by server side language like php,for example in php

$var1 = $_POST['field1']

now I wanna know is it possible to get it by JavaScript to?(or any Client Side Language like VBScript)

for example I have page which has got form

<form method = "post" action="test.php">

in test.php I wanna get field by JavaScript,not by php.
Is it possible and how can I do it if it’s possible?

Answer 1

You cannot read $_POST data using JavaScript.

When you submit data through the GET method, the generated query string can be read through the location.search object. Another method to “post” data from page 1 to page 2 is by using hashes.

The location object (JavaScript)

location.href = http://example.com/test.php?formElem=value&another=true#hash
location.search = ?formElem=value&another=true
location.hash = #hash

Example (based on the URL at the previous paragraph)

<script>
var $_GET = (function(){
    var query_string = location.search.substr(1); //Exclude the first character: `?`
    var data = query_string.split(/&+/); //
    var $_GET = {};
    for(var i=0; i<data.length; i++){
        var qs = data.match(/^([^=]+)(?:=(.*))?$/);
        $_GET[qs[1]] = qs[2];
    }
    return $_GET;
})()

alert($_GET["formElem"]); //Alerts "value"
</script>

An alternative method to transmit data from a form to a JavaScript HTML page is by using hashes:

<form action="index.html#someHash" method="get">
    <input type="submit" name="someName" value="someValue" />
</form>

After submission, the following page will be requested: index.html?someName=someValue#someHash
The hash is available through the location.hash property.