Check if array is empty

Question

The following code shows an array of records in the $rows array from the MySQL query. I have added also an if statement to check if $rows turns up empty, but it is not working.

$rows = array();

$result1 = mysql_query("SELECT * FROM TestPhase where Pid<10", $db) or die("cannot select");
while($row = mysql_fetch_array($result1)) {
  $rows []= array(
    'id' => $row['id'],
    'parent' => $row['parent'],
    'name' => $row['name'],
  );

}


if($rows == ""){
    echo "No Data";

    }

This if statement is not working. How do I check if the array returns empty and echo "No Data".

How would I check to see if the array is empty in javascript? I have placed the $rows array in a var treeData.

if (treeData) is empty{
$("button").hide();
     }

How do I check if treeData is empty to hide the button.

How did you place the data from php into javascript? With json or from php? — Awemo, Sep 25 '12 at 15:20

Havelock · Accepted Answer · 2012-09-26T09:12:56.117

28

PHP
Simply use empty(), i.e.

if(empty($rows)){
    echo 'No Data';
}

Alternatively you could also use count(), i.e.

if(count($rows) < 1){ // or if(count($rows) === 0)
    echo 'No Data';
}

JavaScript
You can use the length property

if(treeData.length == 0){
    $("button").hide();
}

edited Sep 26 '12 at 09:12

answered Sep 25 '12 at 14:46

Havelock

6,913
4
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42

Thanks this worked great. But please see the updated question. How do I do this in javascript? – user1684586 Sep 25 '12 at 15:06

Muthu Kumaran · Answer 2 · 2012-09-25T15:53:25.047

3

Use count to check

if(!count($rows)){
    echo "No Data";
}

Using JavaScript, here is the example

var arr = new Array('one', 'two', 'three'); //assume you have list of values in array
if(!arr.length){ //if no array value exist, show alert()
   alert('No Data');
}

edited Sep 25 '12 at 15:53

answered Sep 25 '12 at 14:46

Muthu Kumaran

17,682
5
47
70

score 1 · Answer 3 · answered Sep 25 '12 at 14:46

1

You can't treat an array like a string (i.e. $rows == ""). Use count() or empty() instead:

if(count($rows) == 0)
{
    echo "No Data";
}

answered Sep 25 '12 at 14:46

BenM

52,573
26
113
168

score 0 · Answer 4 · answered Sep 25 '12 at 14:46

0

Use empty:

if( empty( $rows) ) { ... }

answered Sep 25 '12 at 14:46

moonwave99

21,957
3
43
64

score 0 · Answer 5 · answered Sep 25 '12 at 14:46

0

if ( count( $rows ) == 0 ) {...}

answered Sep 25 '12 at 14:46

Gustav Barkefors

5,016
26
30

Check if array is empty

5 Answers5