HTML表单onsubmit是否可以编辑表单中的文本字段？

Question

I am learning php and html.

I am trying to make a function run when a submit button is pressed. Then I want it to edit a text field on my form with the variable from that function. Without going to a new page...like a self refresh.

How do I do this? Thanks.

I think I have seen how to do this with JavaScript getelementbyID . But I need to do it via php.

Perhaps an easy way to explain it is this: When button is pressed it generates a password in a text field automatically.

The function I am using:

<?
function genkey($length){
    $key = '';
    list($usec, $sec) = explode(' ', microtime());
    mt_srand((float) $sec + ((float) $usec * 100000));

    $possibleinputs = array_merge(range('z','a'),range(0,9),range('A','Z'));

    for($i=0; $i<$length; $i++) {
        $key .= $possibleinputs{mt_rand(0,61)}; }
    return $key;
}
?>

Answer 1

Use ajax to get the password from the php file and update the textfield.

Some sample code using jquery and ajax:

$.ajax({
url : 'ajax.php',
type : 'post',
success : function(data){
$('#password_field').val(data)        
}
});

Answer 2

$.ajax({
    url: "/your_php_page/function", 

    type: "POST",

    data: "parameters you want to post to the function",

    success: function(data){
        $('#input_field_to_be_updated').val(data);
    }

});

Your php function should be echoed the password which you want to place it in input box.

Answer 3

like this:

//    index.php
<?php
function genkey($length){
    $key = '';
list($usec, $sec) = explode(' ', microtime());
mt_srand((float) $sec + ((float) $usec * 100000));

$possibleinputs = array_merge(range('z','a'),range(0,9),range('A','Z'));

for($i=0; $i<$length; $i++) {
    $key .= $possibleinputs{mt_rand(0,61)}; }
return $key;
}

$data = array();
if( !empty($_POST['variable']) ) {
    $data['variable'] = genkey( strlen($_POST['variable']) );
} else {
    $data['variable'] = '';
}
?>
//...HTML...
<form action="" method="POST">
<input name="variable" value="<?=$data['variable']?>">
<input type="submit" value="toPHP">
</form>
//...HTML...

Answer 4

Make a separate php file(keygen.php) with the function.

<?php

$length=$_GET['klength'];

 echo genkey($length);

  function genkey($length){
   $key = '';
  list($usec, $sec) = explode(' ', microtime());
  mt_srand((float) $sec + ((float) $usec * 100000));

$possibleinputs = array_merge(range('z','a'),range(0,9),range('A','Z'));

for($i=0; $i<$length; $i++) {
  $key .= $possibleinputs{mt_rand(0,61)}; }
return $key;
}

?>

Than add this code in your html file

<script src="//ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"    type="text/javascript"></script>

<script type="text/javascript">
 $(document).ready(function() {

$.get('keygen.php?length=32', function(data) {
alert(data)
 });    

});
</script>