PHP + MYSQL6 (page after login)

This is the last page, called the landing page.
Basic code

echo "</table>";
				echo "<br/>";
				echo "<form action='denglucg.php' method='post'>";
				echo "<h2>创建新事项</h2>";
				echo "<label><span>题目</span><input type='text' name='title'></label>";
				echo "<label><span>最后期限</span><input type='text' name='complete-by' value='YYYY-MM-DD'></label>";
				echo "<label><span>描写</span><textarea name='description'></textarea></label>";
				echo "<input type='submit' value='创建新事项'/>";
				echo "</form>";

First open the session technology, you can get the data stored in the server can be obtained

@session_start();

Then see if you have logged in before and have not logged out, and the page after login is displayed, and

$current_userid=$_SESSION['userid'];
$query = "SELECT id, title,mx,ksdate,wcdate from items WHERE user_id = $current_userid";

It means to save the acquired data in a variable, because every time the data consumption performance of the browser is acquired
, all the data in the items is queried. The condition is that the registered user and the logged-in user are consistent and the information of which user is displayed.

$db=new mysqli('localhost','root','','bb');
			$db->set_charset('utf8');
			//看看链接成不成功，
			if ($db->connect_errno) {
				echo "这次链接有问题。,重新登录把";
				exit();
			}

No need to say it, this

Update operation

if(isset($_POST['completed-item'])) {
					$item_id = $_POST['completed-item'];
					$completed_query = "UPDATE items set wcdate= '".date("Y-m-d")."' WHERE id = $item_id";
					$completed_result = $db->query($completed_query);
					if(!$completed_result) {
						echo "没有更新";
						exit();
					}
				}

Insert operation

if(isset($_POST['title'])) {
					$title = $_POST['title'];
					$description = $_POST['description'];
					$complete_by = $_POST['complete-by'];
					$user_id = $_SESSION['userid'];
					$stmt = $db->prepare("INSERT INTO items VALUES (?,?,?,?,?,?)");
					$id = NULL;
					$completed_on = NULL;
					$stmt->bind_param("issssi", $id, $title, $description, $complete_by, $completed_on, $user_id);
					$stmt->execute();
					if(!$stmt->affected_rows) {
						echo "没有插入";
					}
				}

delete data

if(isset($_POST['item-to-delete'])) {
					$item_to_delete = $_POST['item-to-delete'];
					$delete_query = "DELETE FROM items WHERE id = $item_to_delete";
					$delete_result = $db->query($delete_query);
					if(!$delete_result) {
						echo "没有删除";
						exit();
					}
				}

Old rule: field_seek (1); skip the first field. , Why, because the user's id starts from 1
$ result-> fetch_field () gets the field
fetch_assoc () associative array

if($result->num_rows) {
					echo "<table>";
					echo "<caption>我的To-Do List</caption>";
					echo "<thead>";
					echo "<tr>";
					echo "<th>号</th>";
					$result->field_seek(1);
					while($field = $result->fetch_field()) {
						echo "<th>".$field->name."</th>";
					}
					echo "<th>删除</th>";
					echo "</tr>";
					echo "</thead>";
					for($i = 1; ($row = $result->fetch_assoc()); $i++) {
						echo "<tr>";
						echo "<td>$i</td>";
						echo "<td>".$row['title']."</td>";
						echo "<td>".$row['mx']."</td>";
						echo "<td>";
						if(!$row['ksdate']) {
							echo "无最后期限";
						} else {
							echo $row['ksdate'];
						}
						echo "</td>";
						if(!$row['wcdate']) {
							echo "<td>";
							echo "<form action='denglucg.php' method='post'>";
							echo "<input type='hidden' value='".$row['id']."' name='completed-item' />";
							echo "<input type='submit' value='标记为完成了'/>";
							echo "</form>";
							echo "</td>";
						} else {
							echo "<td>".$row['wcdate']."</td>";
						}
						echo "<td>";
							echo "<form action='denglucg.php' method='post'>";
							echo "<input type='hidden' name='item-to-delete' value='".$row['id']."'/>";
							echo "<input type='submit' value='删除'/>";
							echo "</form>";
						echo "</td>";
						echo "</td>";
						echo "</tr>";
					}

				}