我想在提交之前使用javascript从表单中获取价值

Question

I want to get value from input text form and send it to php before submit.

Ex: PHP FILE:

$do="FORM VALUE HERE";     //HERE IS $_POST['search'];
$result = mysql_query("SELECT * FROM table WHERE name='$do'");
while($row = mysql_fetch_array($result))
  {
   $code=$row['code_number'];
  }

HTML:

<script >
HERE WHAT I WANT TO DO
<script />

FORM:

<form action="view_results.php?code=<? echo $code ?>" method="post">
<input type="text" name="search" /><br />
<input type="submit" value="search" />
<form />

So, with this example I want to get $do=$_POST['search'] before clicking to submit botton so I can select the result from mySQL to view it in the next page.

Thanks

Answer 1

You can catch the form's submit event, cancel it, grab the form value you want, make your PHP post, and when that's done, go back and submit your form.

<form id="form1" action="view_results.php?code=<? echo $code ?>" method="post">

document.forms["form1"].onsubmit = function(e) {
    e.preventDefault(); //cancel form submit

    var searchValue = this.search.value;

    var self = this;
    //post searchValue to your PHP page using your favorite JS library, 
    //then in the call back, submit your form with self.submit();
};

Answer 2

<form action="view_results.php?code=<? echo $code ?>" method="post" onsubmit="beforeSubmit(event)">
   <input type="text" name="search" /><br />
   <input type="submit" value="search" />
<form />

<script >
   //HERE WHAT I WANT TO DO

   function beforeSubmit(event){

       event.preventDefault();

       var form = event.currentTarget;

       // form.search.value will give the text in search

   }
<script />