HTML form string error [closed]

问题

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Closed 6 years ago.

When I click the "Send "Request" button, the query string ?req_flag=0 disappears from the URL. Where am I making a mistake here? I need following URL: localhost/flavourr/send_req.php?req_flag=0&f_e_mail_add=value

<pre>
<form method="get" action="send_req.php?req_flag=0">
                        <input type="text" name="f_e_mail_add" value="Enter email of your friend" onblur='if (this.value == "") {this.value = "Enter email of your friend";}' onfocus='if (this.value == "Enter email of your friend") {this.value = "";}' size="35" />
                        <input type="submit" value="Send Request" />
                            </form></pre>

回答1:

Just add a hidden value as shown below and remove the '?req_flag=0' from the action attribute.

<form method="get" action="send_req.php">
    <input type="text" name="f_e_mail_add" value="Enter email of your friend" size="35" />
    <input type="hidden" id="req_flag" name="req_flag" value="0" />
    <input type="submit" value="Send Request" />
</form>

回答2:

If your page gets that parameter from another source you can't simply transfer a GET parameter from one page to another. You have to find a way for your new form to include that parameter again before submitting the form.

The easiest way is to store it inside a hidden input element like this.

<input type="hidden" name="req_flag" value="<?php echo htmlentities($_GET['req_flag'], ENT_QUOTES, 'utf-8'); ?>" />

来源：https://stackoverflow.com/questions/6779966/html-form-string-error