prevent form submit with empty input?

Question

Possible Duplicate:
How to prevent submitting the HTML form’s input field value if it empty

<?php

include '../core/init.php';
if(isset($_POST['nt']) && isset($_POST['ntb'])){
mysql_query("INSERT INTO `post` (`myid`, `text`) VALUES ('".$_SESSION['id']."', '".mysql_real_escape_string($_POST['nt'])."')");
}
?>

<iframe style="display:none" name="submissiontarget" id="submissiontarget"></iframe>
<form method="post" target="submissiontarget" action = "../ajax/post.php" name="form">
<input type="textbox" name="nt" class="postwall" id="nt"  placeholder="Post on your wall" rows="7" wrap="physical" cols="40" onfocus="if(this.value=='Post On Your Wall')this.value='';" onblur="if(this.value=='')this.value='Post On Your Wall';" />
<input type="submit" style="display:none;" name='ntb' id='ntb'  class="Buttonchat"     value="Post" />
</form>

I want to be able to do it so if the textbox is blank it says, 'Their was an error posting on your wall, please try again'.

possible duplicate of [How to prevent submitting the HTML form's input field value if it empty](http://stackoverflow.com/questions/8029532/how-to-prevent-submitting-the-html-forms-input-field-value-if-it-empty) (…or any similar question here on SO; e.g. http://stackoverflow.com/questions/10516122/how-prevent-submit-if-input-are-empty-with-javascript) — feeela, Dec 01 '12 at 20:33
not hard to research basic form validation in a simple web search. At least show a little effort before posting a question here — charlietfl, Dec 01 '12 at 20:45

score 0 · Answer 1 · answered Dec 01 '12 at 20:38

if(isset($_POST['nt']) && isset($_POST['ntb'])) {
    …
} else {
    echo "There was an error posting on your wall, please try again.";
}

The catching of empty input submits on clientside, as demonstrated in the duplicate, might be an additional feature, but you won't get around doing it serverside.

prevent form submit with empty input?

1 Answers1

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