I am trying to implement a quick search bar to search a table populated by an SQL database. The search will not search the table, but will generate SQL statements and search the database. I need to implement a search function using PHP that will use flags to stop the search. This is my code so far:
//THIS CODE WILL EXECUTE WHEN THE SEARCH BUTTON IS PRESSED
if($_REQUEST['btnsearch']){
if(isset($_POST['quicksearch']) and !empty($quicksearch)){
$sql = "SELECT column_name FROM information_schema.columns WHERE table_name ='alerts_table'
AND column_name IN('name', 'year','make','model','alert','date')";
$retvalues = mysqli_query($conn, $sql);
$data = array();
//LOOP POPULATES THE ARRAY WITH THE CURRENT COLUMN NAMES.
for($counter = 0; $counter <= $row=mysqli_fetch_array($retvalues, MYSQL_ASSOC); $counter++){
$string = $row["column_name"];
$data[$counter] = $string;
}
$length = count($data);
$flag = 1;
while($flag == 1){
for($x = 0; $x <= $length - 1; $x++){
$sql3="SELECT * FROM alerts_table WHERE $data[$x] = $quicksearch";
$retvalues2=mysqli_query($conn, $sql3);
if(!empty($retvalues2))
{
//POPULATE THE TABLE WITH RESULTS HERE !!!!!!!!!
$flag = -1; ///HOW CAN I BREAK THE LOOP???
}
}
}
}else{
From the PHP break documentation:
(PHP 4, PHP 5, PHP 7)
break ends execution of the current for, foreach, while, do-while or
switch structure.
break accepts an optional numeric argument which tells it how many
nested enclosing structures are to be broken out of. The default value
is 1, only the immediate enclosing structure is broken out of.
In your case you have two loops; a while loop and an inner for loop. You can set your flag in your inner loop to a value that will stop the while loop, and then use a break to stop the for loop.
$flag = 1;
while($flag == 1){
for($x = 0; $x <= $length - 1; $x++){
// ...
if(!empty($retvalues2))
{
$flag = -1; // set while condition to false
break; // break out of for loop
}
}
// execution continues here after break
// end of while body, start next loop iteration
// $flag == 1 => false, and the while loop will end
}
Related
I have an issue. I need to out from inner loop once DB will be updated using PHP but in my case its not happening like this. I am explaining my code below.
for ($i=0; $i < count($result); $i++) {
for ($j=0; $j < 4; $j++) {
$index=$j+1;
$up_sql=" file".$index."='".$result[$i]['img']."' ";
$sqlget=mysqli_query($connect,"select * from cn_sell_info where file".$index."= '' and sid =".$sid);
if(mysqli_num_rows($sqlget) > 0){
$update="update cn_sell_info set ".$up_sql." where sid=".$sid ;
$upsql2=mysqli_query($connect,$update);
break;
}
}
}
Here I have put break statement still same value is updated in cosucative columns as per code. I need once table will updated it will come out from inner for loop means again first for loop will execute again.Please help me.
Break has an optional parameter which indicates the number of levels to break out of. so break is equivalent to break 1. But you can do break 2 which breaks out of two levels of nesting.
$i = 0;
while (++$i) {
switch ($i) {
case 5:
echo "At 5<br />\n";
break 1; /* Exit only the switch. */
case 10:
echo "At 10; quitting<br />\n";
break 2; /* Exit the switch and the while. */
default:
break;
}
}
?>
Above is from http://php.net/manual/en/control-structures.break.php which gives good examples.
Instead of using break, you can use while loops with natural exit conditions. You don't need to calculate $up_sql every time, do it once inside the if (it's included in query below).
$num_rows = 0;
$i = 0;
while ($i < count($result) && !$num_rows) {
$j = 0;
while ($j < 4 && !$num_rows) {
$index = $j + 1;
$sqlget = mysqli_query($connect, "select * from cn_sell_info where file{$index} = '' and sid = {$sid}");
$num_rows = mysqli_num_rows($sqlget)
if ($num_rows) {
$update = "update cn_sell_info set file{$index}='{$result[$i]['img']}' where sid={$sid}";
$upsql2 = mysqli_query($connect, $update);
}
$j++;
}
$i++;
}
So, I want to distribute evenly lists across 3 columns. The lists cannot be broken up or reordered.
At the moment, I have 5 lists each containing respectively 4, 4, 6, 3 and 3 items.
My initial approach was:
$lists = [4,4,6,3,3];
$columns = 3;
$total_links = 20;
$items_per_column = ceil($total_links/$columns);
$current_column = 1;
$counter = 0;
$lists_by_column = [];
foreach ($lists as $total_items) {
$counter += $total_items;
$lists_by_column[$current_column][] = $total_items;
if ($counter > $current_column*$links_per_column) {
$current_column++;
}
}
Results in:
[
[4],
[4,6],
[3,3]
]
But, I want it to look like this:
[
[4,4],
[6],
[3,3]
]
I want to always have the least possible variation in length between the columns.
Other examples of expected results:
[6,4,4,6] => [[6], [4,4], [6]]
[4,4,4,4,6] => [[4,4], [4,4], [6]]
[10,4,4,3,5] => [[10], [4,4], [3,5]]
[2,2,4,6,4,3,3,3] => [[2,2,4], [6,4], [3,3,3]]
Roughly what you need to do is loop over the number of columns within your foreach(). That will distribute them for you.
$numrows = ceil(count($lists) / $columns);
$thisrow = 1;
foreach ($lists as $total_items) {
if($thisrow < $numrows){
for($i = 1; $i <= $columns; $i++){
$lists_by_column[$i][] = $total_items;
}
}else{
//this is the last row
//find out how many columns need to fit.
//1 column is easy, it goes in the first column
//2 columns is when you'll need to skip the middle one
//3 columns is easy because it's full
}
$thisrow++;
}
This will be an even distribution, from left to right. But you actually want a modified even distribution that will look symmetrical to the eye. So within the foreach loop, you'll need to keep track of 1.) if you're on the last row of three, and 2.) if there are 2 remainders, to have it skip col2 and push to col3 instead. You'll need to set that up to be able to play around with it,...but you're just a couple of logic gates away from the land of milk and honey.
So, I ended up using this code:
$lists = [4,4,6,3,3];
$columns = 3;
$total_links = 20;
$items_per_column = ceil($total_links/$columns);
$current_column = 1;
$lists_by_column = [];
for ($i = 0; $i < count($lists); $i++) {
$total = $lists[$i];
$lists_by_column[$current_column][] = $lists[$i];
//Loop until reaching the end of the column
while ($total < $items_per_column && $i+1 < count($lists)) {
if ($total + $lists[$i+1] > $items_per_column) {
break;
}
$i++;
$total += $lists[$i];
$lists_by_column[$current_column][] = $lists[$i];
}
//When exiting the loop the last time we need another break
if (!isset($lists[$i+1])) {break;}
//If the last item goes onto the next column
if (abs($total - $items_per_column) < abs($total + $lists[$i+1] - $items_per_column)) {
$current_column++;
//If the last item goes onto the current column
} else if ($total + $lists[$i+1] > $items_per_column) {
$i++;
$lists_by_column[$current_column][] = $lists[$i];
$current_column++;
}
}
I'm looking to increment a number after a certain letter.
I have a list of own Ids and i would like to increment it without write it manually each time i add a new id.
$ids = array('303.L1', '303.L2', '303.L3', '303.L4');
so i use the END() function to extract the last id from this array.
this is what i've tried but i cannot get a result.
$i = 0;
while($i <= count($ids)){
$i++;
$new_increment_id = 1;
$final_increment = end($last_id) + $new_increment_id;
}
echo $final_increment;
New method, but it is adding me double dot between number and letter.
$i = 0;
while($i <= count($ids)){
$i++;
$chars = preg_split("/[0-9]+/", end($ids));
$nums = preg_split("/[a-zA-Z]+/", end($ids));
$increment = $nums[1] + 1;
$final_increment = $nums[0].$chars[1].$increment;
}
//i will use this id to be inserted to database as id:
echo $final_increment;
Is there another way to increment the last number after L ?
Any help is appreciated.
If you don't want a predefined list, but you want a defined number of ids returned in an $ids variable u can use the following code
<?php
$i = 0;
$number_of_ids = 4;
$id_prefix = "303.L";
$ids = array();
while($i < $number_of_ids){
$ids[] = $id_prefix . (++$i); // adds prefix and number to array ids.
}
var_dump($ids);
// will output '303.L1', '303.L2', '303.L3', '303.L4'
?>
I'm a bit confused because you say "without write it manually". But I think I have a solution:
$ids = array('303.L1', '303.L2', '303.L3', '303.L4');
$i = 0;
while($i <= count($ids)){
++$i;
//Adding a new item to that array
$ids[] = "303.L" . $i;
}
This would increment just that LAST number, starting at zero. If you wanted to continue where you left off, that'd be simple too. Just take $i = 0; and replace with:
//Grab last item in array
$current_index = $ids[count($ids) - 1];
//Separates the string (i.e. '303.L1') into an array of ['303', '1']
$exploded_id = explode('.L', $current_index);
//Then we just grab the second item in the array (index 1)
$i = $exploded_id[1];
Newb question: I'm using a foreach loop to get items from an array.
I need to start looping at an offset number- (I'm using a $i variable to do this, no problem).
But when my foreach reaches the end of the array I want it to start going through the array again until it reaches the offset number.
I need to do this so I can have a user open any image in an artist's portfolio and have this image used as the first image presented in a grid of thumbnail icons , with all the other images subsequently populating the rest of the grid.
Any ideas?
Please bear in mind I'm new to PHP! :)
See below for an example of my current code...
$i=0;
$limit=50;// install this in the if conditional with the offset in it (below) to limit the number of thumbnails added to the page.
$offset=$any_arbitrary_link_dependant_integer;
foreach($portfolio_image_array as $k=>$image_obj){//$k = an integer counter, $image_obj = one of the many stored imageObject arrays.
$i++;
if ($i > $offset && $i < $limit) {// ignore all portfolio_array items below the offset number.
if ($img_obj->boolean_test_thing===true) {// OK as a way to test equivalency?
// do something
} else if ($img_obj->boolean_test_thing===false) { // Now add all the non-see_more small thumbnails:
// do something else
} else {
// error handler will go here.
}
} // end of offset conditional
}// end of add boolean_test_thing thumbnails foreach loop.
};// end of add thumbnails loop.
$i = 0;
$limit = 50;
$offset = $any_arbitrary_link_dependant_integer;
$count = count($portfolio_image_array);
foreach($portfolio_image_array as $k=>$image_obj){//$k = an integer counter, $image_obj = one of the many stored imageObject arrays.
$i++;
if ($i > $offset && $i < $limit && $i < ($count - $offset)) {// ignore all portfolio_array items below the offset number.
if ($img_obj->boolean_test_thing===true) {// OK as a way to test equivalency?
// do something
} else if ($img_obj->boolean_test_thing===false) { // Now add all the non-see_more small thumbnails:
// do something else
} else {
// error handler will go here.
}
} // end of offset conditional
}// end of add boolean_test_thing thumbnails foreach loop.
};
Only thing I added was a $count variable.
Edit: If your array starts at 0 I would suggest you put the $i++; at the end of your foreach loop.
A simple method is to use two separate numeric for loops, the first going from offset to end, and the second going from beginning to offset.
<?php
// Create an example array - ignore this line
$example = array(1,2,3,4,5,6);
$offset = 3;
// Standard loop stuff
$count = count($example);
for($i = $offset; $i < $count; $i++)
{
echo $example[$i]."<br />";
}
for($i = 0; $i < $offset; $i++)
{
echo $example[$i]."<br />";
}
?>
This is also almost certainly cheaper than doing multiple checks on every single element in the array, and it expresses exactly what you are trying to do to other programmers who look at this code - including yourself in 2 weeks time.
Edit: depending on the nature of the array, in order to use numeric keys you may first need to do $example = array_values($portfolio_image_array);.
Using Answer Question to force StackOverflow to let me post a decent length of text!
OK #Mark Walet et al, not sure how to post correctly on this forum yet but here goes. I got the issue sorted as follows:
$i=0;
$offset=$image_to_display_number;
$array_length = count($portfolio_image_array);
// FIRST HALF LOOP:
foreach($portfolio_image_array as $k=>$img_obj){// go through array from offset (chosen image) to end.
if ($i >= $offset && $i <= $array_length) {
echo write_thumbnails_fun($type_of_thumbnail, $image_path, $k, $i, $portfolio_image_array, $title, $image_original);
$t_total++;// update thumbnail total count.
}
$i++;
}// end of foreach loop 1.
$looped=true;// Just FYI.
$i=0;// Reset.
// SECOND HALF LOOP:
foreach($portfolio_image_array as $k=>$img_obj){// go through array from beginning to offset.
if ($i < $offset) {
echo write_thumbnails_fun($type_of_thumbnail, $image_path, $k, $i, $portfolio_image_array, $title, $image_original);
}
$i++;
}// end of foreach loop 2.
Thankyou so much for all the help!
:)
as #arkascha suggested use modulo operator
<?php
$example = array(1,2,3,4,5,6);
$count = count($example);
$offset = 3;
for($i = 0; $i < $count; $i++) {
$idx = ($offset + $i) % count
echo $example[$idx]."<br />";
}
?>
Ive managed to loop through a table and get the difference in days between 2 dates adjacent to each other in the table.
Multiple entries have the same date, i have it now that when that date changes, it displays an image however i want it to display the image as many times as the difference in date
$sql = mysql_query("SELECT * FROM Films_Info")
or die(mysql_error());
$last_value = null;
while ($row = mysql_fetch_assoc($sql)) {
if (!is_null($last_value)) {
$a = new DateTime($row['FilmRelease']);
echo "<p>".$row['FilmName']."</p>";
$interval = $a->diff(new DateTime($last_value));
//echo $interval->format('%d days');
$i = 0;
}
$howManydays = $interval->days;
for ( $i; $howManydays; $i++) {
echo "<img src=\"day.jpg\" />";
$howManydays = 0;
}
$last_value = $row['FilmRelease'];
}
for ( $i = 0; $i < $howManydays; $i++) The second is a conditional statement telling when the loop should stop.
The first section in the for loop where it says $i = 0 initialized the variable $i to 0 and then tests the condition $i < $howManydays.
Let's say $howManydays equals 1. That means 0 < 1, so the loop will perform.
At the end of the loop, the third section is called ($i++), so $i is incremented and now equals 1. The second section is called again to test conditions $i < $howManydays which is asking if 1<1 which it's not, so the loop will exit.
So if $howManydays is greater than 0, the loop should happen the integer amount that is in $howManydays.
You will want to remove $howManydays = 0; within the for loop, if you don't want it to only fire once.
The for loop
for ( $i = 0; $i < $howManydays; $i++){
// ...
}
is somewhat equivalent to the while loop:
$i = 0;
while ( $i < $howManydays ){
// ...
$i++;
}
http://php.net/manual/en/control-structures.for.php for more information
In your code above, you should also check if interval was set. You should probably just do an if rather than a while, if only need one interval.
you could just do a simple division on the interval and print out the image that many times
$last_value_u = $last_value->format('U');
$a_u = $a->format('U');
$interval = $a_u - $last_value_u;
$image_count = intval($interval/86400);
for($i=0;$i<$image_count;$i++)
echo "<p><img src=\"day.jpg\" /></p>";
Update
An alternative option would be to loop through the interval:
for($i=$last_value_u;$i<$a_u;)
{
if(intval(($a_u - $i)/86400) == X)
{
// run special code for specific day
}
else
{
// run code for every other day
}
$i+=86400;
}