Submit FORM data then return response

Question

I have the following code which sends post data to my form and alerts the expected result, however I'm finding it hard to save this as a variable I can use outside the function, can anyone offer any help?

<script>
var http = new XMLHttpRequest();
var url = "form.php";
var params = "name=test";
http.open("POST", url, true);

//Send the proper header information along with the request
http.setRequestHeader("Content-type", "application/x-www-form-urlencoded");

http.onreadystatechange = function() {//Call a function when the state changes.
    if(http.readyState == 4 && http.status == 200) {
        alert(http.responseText);
    }
}
http.(params);
</script>

What is the responseText ? Is it json ? – lucky Jan 20 '18 at 12:32 — lucky, Jan 20 '18 at 12:32
The HTML response from the webpage – Hugh Jan 20 '18 at 12:33 — Hugh, Jan 20 '18 at 12:33

score 0 · Answer 1 · answered Jan 20 '18 at 12:35

0

Just declare a variable and set it when the request responsed by server;

var http = new XMLHttpRequest();
var url = "form.php";
var params = "name=test";
var response;
http.open("POST", url, true);

//Send the proper header information along with the request
http.setRequestHeader("Content-type", "application/x-www-form-urlencoded");

http.onreadystatechange = function() {//Call a function when the state changes.
    if(http.readyState == 4 && http.status == 200) {
        alert(http.responseText);
        response = http.responseText;
    }
}
http.(params);

answered Jan 20 '18 at 12:35

lucky

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alert(http) and alert(response) both return "undefinied". Am I missing something? Apologies, I'm relatively new to Javascript – Hugh Jan 20 '18 at 12:41
Is it typo "http.(params);" -> http.send(params); – lucky Jan 20 '18 at 12:52
Even when I do that, doing alert(response) returns "undefined" – Hugh Jan 20 '18 at 13:00

Submit FORM data then return response

1 Answers1