How to get value from php to input using ajax request [duplicate]

问题

Hi My question is how can I get the value from php script using an ajax with a onclick event.

I have a text field and a button

<button type="button" class="btn btn-primary" onclick="getid(this)">Generate ID</button>
<input type="text" name="pin" class="form-control" readonly>

And here is my php script named getrowcount.php

include_once  'conx.php';

$query ="SELECT * FROM patientprofile";
$result = $DBcon->query($query);
$count = $result->num_rows;

if ($result) {
   if($count >= 0){
       $count_res = $count += 1;
       $idnum = $count_res;
       $test = str_pad($idnum, 5, "0", STR_PAD_LEFT);
    }
}

And now my problem is how can I get the value from $test and put it in the input text field using ajax.

回答1:

You can use AJAX to display the output from the query in the input field.

Step 1: Add this line of code to the bottom of getrowcount.php:

echo $test;

Step 2: Amend your HTML so that it looks like this:

<form id="get">
   <input type="text" id="pin" name="pin" class="form-control" readonly>
   <input type="submit" class="btn btn-primary" value="Generate ID">
</form>

Step 3: Add this script to the bottom of the page.

<script>
$(document).ready(function(){
    $("form#get").submit(function(event) {
        event.preventDefault();
        var input = $("#pin");

        $.ajax({
            type: "POST",
            url: "getrowcount.php",
            success: function(data) { input.val(data); }
        });
    });
});
</script>

回答2:

May be this will help you

Your PHP code :

<?php
    // Your database query and results store in $test
    echo $test;
?>

Your ajax call should be -

$.ajax("getrowcount.php").done(function(data) {
   $('.form-control').val(data);
})

回答3:

You could use the jQuery method $.get() in your javascript script :

function getid(_this){
     $.get('php_script_url.php',{},function(response){
         alert(response);
         $("[name=pin]").val(response);
     })
}

Then in your PHP script you should add echo to the result you want to return :

echo $test;

Hope this helps.

回答4:

For this you'd run the ajax call on button press, load the php from the ajax, in the php do an echo with the variable you want to use, then in the ajax success section, you'd use the returned variable.

来源：https://stackoverflow.com/questions/41964536/how-to-get-value-from-php-to-input-using-ajax-request

标签

javascript

php

jquery

ajax

ajaxform