pagination using Rest API in php - php

Question

I am trying to fetch data from mysql and display them category wise with pagination. I am getting the category wise result but when i change my page data of every category changed too i need to change the data of only category selected . i have setup multi category news option for user so they can add one news to multiple category .help me out here is my code what am trying.
<?php
include'../config.php';
// number of rows to show per page
$rowsperpage = 2;
$main = array();
$cat = array();
$qry = "SELECT * FROM app_category order by id DESC ";
$res = mysqli_query($con, $qry);
$records = mysqli_fetch_array($res, MYSQLI_ASSOC);
$rowcount = mysqli_num_rows($res);
if ($rowcount > 1) {
foreach ($res as $records) {
$cat = $records;
// lets find out how many rows are in the MySQL table
$sql = "SELECT COUNT(*) FROM app_news WHERE cat_id='" . $cat['id'] . "'";
$result = mysqli_query($con, $sql) or die(mysql_error());
$r = mysqli_fetch_row($result);
$numrows = $r[0];
// find out total pages
$totalpages = ceil($numrows / $rowsperpage);
if (isset($_GET['currentpage']) && is_numeric($_GET['currentpage'])) {
$currentpage = (int) $_GET['currentpage'];
} else {
$currentpage = 1; // default page number
}
// if current page is greater than total pages
if ($currentpage > $totalpages) {
// set current page to last page
$currentpage = $totalpages;
}
// if current page is less than first page
if ($currentpage < 1) {
// set current page to first page
$currentpage = 1;
}
// the offset of the list, based on current page
$offset = ($currentpage - 1) * $rowsperpage;
$qry = "SELECT * FROM app_news where cat_id='" . $cat['id'] . "' LIMIT $offset, $rowsperpage";
$res1 = mysqli_query($con, $qry);
$json1 = array();
while ($records1 = mysqli_fetch_array($res1, MYSQLI_ASSOC)) {
$news_id = $records1['news_id'];
$news_title = $records1['title'];
$news_des = $records1['description'];
$news_des = htmlspecialchars_decode(str_replace(""", "\"", $news_des));
$news_image = $records1['image'];
$json1[] = array("news_id" => $news_id, "title" => $news_title, "image" => $imgapi . $news_image, "description" => $news_des);
}
$cat['All-news'] = array("total no of pages" => $totalpages, "data" => $json1);
$main[] = $cat;
unset($json1);
unset($json);
unset($cat);
}
unset($totalpages);
//header("Content-Type: application/json; charset=utf-8");
echo json_encode($main, JSON_UNESCAPED_SLASHES);
unset($main);
mysqli_close($con);
} else {
$minfo = array("success" => 'false', "message" => 'No result to display. Please add First category.');
$jsondata = json_encode($minfo);
print_r($jsondata);
mysqli_close($conn);
exit();
}

Answer 1

I have Split my code in two request get and post
get is for first time initialisation and then i use post method for getting scroll amount from app:
here is code :
<?php
include'../config.php';
$main = array();
$cat = array();
if ($_SERVER['REQUEST_METHOD'] === 'GET') {
$rowsperpage = 5;
$qry = "SELECT * FROM app_category order by id DESC ";
$res = mysqli_query($con, $qry);
$records = mysqli_fetch_array($res, MYSQLI_ASSOC);
$rowcount = mysqli_num_rows($res);
if ($rowcount > 1) {
foreach ($res as $records) {
$cat = $records;
// lets find out how many rows are in the MySQL table
$sql = "SELECT COUNT(*) FROM app_news WHERE cat_id='" . $cat['id'] . "'";
$result = mysqli_query($con, $sql) or die(mysql_error());
$r = mysqli_fetch_row($result);
$numrows = $r[0];
// find out total pages
$totalpages = ceil($numrows / $rowsperpage);
if (isset($_GET['currentpage']) && is_numeric($_GET['currentpage'])) {
$currentpage = (int) $_GET['currentpage'];
} else {
$currentpage = 1; // default page number
}
// if current page is greater than total pages
if ($currentpage > $totalpages) {
// set current page to last page
$currentpage = $totalpages;
}
// if current page is less than first page
if ($currentpage < 1) {
// set current page to first page
$currentpage = 1;
}
// the offset of the list, based on current page
$offset = ($currentpage - 1) * $rowsperpage;
$qry = "SELECT * FROM app_news where cat_id='" . $cat['id'] . "' LIMIT $offset, $rowsperpage";
$res1 = mysqli_query($con, $qry);
$json1 = array();
while ($records1 = mysqli_fetch_array($res1, MYSQLI_ASSOC)) {
$news_id = $records1['news_id'];
$news_title = $records1['title'];
$news_des = $records1['description'];
$news_des = htmlspecialchars_decode(str_replace(""", "\"", $news_des));
$news_image = $records1['image'];
$json1[] = array("news_id" => $news_id, "title" => $news_title, "image" => $imgapi . $news_image, "description" => $news_des);
}
$cat['All-news'] = array("total no of pages" => $totalpages, "data" => $json1);
$main[] = $cat;
unset($json1);
unset($json);
unset($cat);
}
unset($totalpages);
//header("Content-Type: application/json; charset=utf-8");
echo json_encode($main, JSON_UNESCAPED_SLASHES);
unset($main);
mysqli_close($con);
} else {
$minfo = array("success" => 'false', "message" => 'No result to display. Please add First category.');
$jsondata = json_encode($minfo);
print_r($jsondata);
mysqli_close($conn);
exit();
}
}
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
include_once'../config.php';
if (isset($_POST['cat_id'])) {
$rowsperpage = 5;
$catid = $_POST['cat_id'];
$qry = "SELECT * FROM app_category WHERE id='" . $catid . "' ";
$res = mysqli_query($con, $qry);
while ($row = mysqli_fetch_array($res, MYSQLI_ASSOC)) {
$cat=$row;
}
// lets find out how many rows are in the MySQL table
$sql = "SELECT COUNT(*) FROM app_news WHERE cat_id='" . $cat['id'] . "'";
$result = mysqli_query($con, $sql) or die(mysql_error());
$r = mysqli_fetch_row($result);
$numrows = $r[0];
// find out total pages
$totalpages = ceil($numrows / $rowsperpage);
///Checkeing for page requested
if (isset($_POST['currentpage']) && is_numeric($_POST['currentpage'])) {
$currentpage = (int) $_POST['currentpage'];
} else {
$currentpage = 1; // default page number
}
// if current page is greater than total pages
if ($currentpage > $totalpages) {
// set current page to last page
$currentpage = $totalpages;
}
// if current page is less than first page
if ($currentpage < 1) {
// set current page to first page
$currentpage = 1;
}
// the offset of the list, based on current page
$offset = ($currentpage - 1) * $rowsperpage;
$qry = "SELECT * FROM app_news where cat_id='" . $catid . "' LIMIT $offset, $rowsperpage";
$res1 = mysqli_query($con, $qry);
$json1 = array();
while ($records1 = mysqli_fetch_array($res1, MYSQLI_ASSOC)) {
$news_id = $records1['news_id'];
$news_title = $records1['title'];
$news_des = $records1['description'];
$news_des = htmlspecialchars_decode(str_replace(""", "\"", $news_des));
$news_image = $records1['image'];
$json1[] = array("news_id" => $news_id, "title" => $news_title, "image" => $imgapi . $news_image, "description" => $news_des);
}
$cat['All-news'] = array("total no of pages" => $totalpages, "data" => $json1);
$main[] = $cat;
unset($json1);
unset($json);
unset($cat);
echo json_encode($main, JSON_UNESCAPED_SLASHES);
unset($main);
unset($totalpages);
mysqli_close($con);
}
}