How to prevent a "space" from searching MySQL database? - php

Question

Currently, when someone just hits the space key and hits enter it will go to the next page but not search anything - I want to prevent the search altogether. What is the best way to accomplish this? I don't want to prevent spaces from being used (ie: How do I fix this?) - I just dont want spaces themselves to allow a search.

Answer 1

Wrap your query variable in an empty condition:
if(!empty(trim($_POST['searchterm']))
{
// do search
}

Answer 2

Use JavaScript and trim leading spaces in the submit (onsubmit) event handler:
var searchField = document.getElementById('search'); // or whatever the id of the field is
if(searchField.value.replace(/^\s+/, '').length === 0) {
return false; // or evt.preventDefault().
}
It should be okay to rely on client-side validation here because if the user wants to fool the search engine then they won't mind being brought to a blank page. If there's an actual server-side problem in allowing this, then perform the same check server-side:
if(!isset($_REQUEST['search']) || !trim($_REQUEST['search'])) {
// Don't perform the search
}

Answer 3

In addition to #AlienWebguy answer you can use JavaScript to do client side validation in order to stop the page from even getting to the back end. Its definitely a good practice to do the validation on the client side AND server side.
Live Demo
form.onsubmit = function(){
if(input.value.replace(/^\s/,"").length === 0){
return false;
}
}

Answer 4

Just take the string, trim the initial and final spaces and check the length; if length is 0, don't submit the form.

Answer 5

If you are procecssing it with php on the backend you can just use trim($input), but for a better user experince use javascript. Set a form validator so it won't submit unless there is something other than whitespace.
<form onsubmit="return verify()">
<input id="foo" name="foo" />
<input type="submit" />c
</form>
<script type="text/javascript">
function verify() {
if (document.getElementById("foo").value.match(/[^\s]/) == null) {
alert('only whitespace');
return false;
} else {
alert('found substance');
return true;
}
}
</script>