PHP modify user information

【Foreword】

    This article mainly summarizes the function of editing user information in PHP. The principle is very simple, but the syntax requirements must be correct. The author encountered a lot of problems in the writing process, many of which were syntax parsing errors caused by symbols. record here

 

【Step on the pit】

(1) Connect the string , because the field types such as name are char string types, so when parsing, add ' ' quotation marks outside.

         So it should be written as name=' "$_POST['name']" ', so that it can be parsed into the form of name='name'

$sql = "update demo set name='".$_POST['username']."',age='".$_POST['userage']."'
        where id=".$_POST['userid'];

(2) The mysqli_fetch_assoc() function obtains a row from the result set as an associative array  and takes a record

(3) The input box of the hidden ID is often used to pass values, <input type='hidden' name='id'> 

 

 

【Code】

<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>  
<?php
    //connect to the user database
    include 'config.php';
    $connect = mysqli_connect(DB_HOST,DB_USER,DB_PWD,DB_NAME);
    if(!$connect){
        die("could not connect:".mysqli_error());
    }else{
        echo "Connection succeeded<br>";
         //search result
        // The mysqli_query() function executes a MySQL query
        $result = mysqli_query($connect,"select* from user");
        //mysqli_num_rows The number of rows in the result set, which is obtained from the call to mysql_query()
        $count = mysqli_num_rows($result);
        //If you pass a page, change it to an integer
        $page = isset($_GET['page'])?(int)$_GET['page']:1;
        //Number of displays per page
        $num = 5 ;
        //total pages
        $total = ceil($count / $num);
        if ($page<1) {
            $page = 1;
        }
        if ($page>$total) {
            $page = $total;
        }
        //Offset
        $offset = ($page-1)*$num;
        $sql = "select id,name,age from demo order by id asc limit $offset,$num";
        $result = mysqli_query($connect,$sql);
            if ($result&&mysqli_num_rows($result)) {
                echo "<table border=1 cellspacing=0 class='demo'>";
            while($row = mysqli_fetch_array($result)){
                echo "<tr>";
                echo "<td>"."<input type='checkbox'>".$row['id']."</td>";
                echo "<td>".$row['name']."</td>";
                echo "<td>".$row['age']."</td>";
                echo "<td><a href='delete.php?id=".$row['id']."'>删除用户</a></td>";
                echo "<td><a href='edit.php?id=".$row['id']."'>编辑用户</a></td>";
                echo "<tr/>";
            }
            echo'<tr>
                    <td colspan="5">
                        <a href="index.php?page=1">首页</a>
                        <a href="index.php?page=' .($page-1). '">上一页</a>
                        <a href="index.php?page=' .($page+1). '">下一页</a>
                        <a href="index.php?page=' .$total. '">尾页</a>
                        The current page is '.$page.' of '.$total.'
                    </td>
                </tr>';
            echo "</table>";
            echo "<button onclick=''>删除</button>";
        }else{
            echo "No data";
        }
    }
    //close the connection
    $close = mysqli_close($connect);
    if(!$close){
        die("Failed to close the database");
    }else{
        echo "Close successfully";
    }
?>

 

<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>


<?php
//connect to the user database
    include 'config.php';
    $connect = mysqli_connect(DB_HOST,DB_USER,DB_PWD,DB_NAME);
    if(!$connect){
        die("could not connect:".mysqli_error());
    }else{
        //edit user list
        if (is_numeric($_GET['id'])) {
            $id = (int) $_GET['id'];
        }
        $sql = "select id,name,age from demo where id =".$id;
        $result = mysqli_query($connect,$sql);
        $data = mysqli_fetch_assoc($result);
    }
    //close the connection
    $close = mysqli_close($connect);
    if(!$close){
        die("Failed to close the database");
    }else{
        echo "Close successfully";
    }

?>

<form action="change.php" method="post">
    用户名：<input type="text" name="username" value="<?php echo $data['name'];?>"><br>
    年龄:<input type="text" name="userage" value="<?php echo $data['age'] ?>"><br>
    <input type="hidden" name="userid" value="<?php echo $data['id']?>">
    <input type="submit">

</form>

 

<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>


<?php
//connect to the user database
    include 'config.php';
    $connect = mysqli_connect(DB_HOST,DB_USER,DB_PWD,DB_NAME);
    if(!$connect){
        die("could not connect:".mysqli_error());
    }else{
        // echo $_POST['userid'];
        $id = (int) $_POST['userid'];
        if (trim($_POST['username'])&&trim($_POST['userage'])) {
            $sql = "update demo set name='".$_POST['username']."',age='".$_POST['userage']."' where id=".$_POST['userid'];
            $result = mysqli_query($connect,$sql);
            if($result){
                echo "Modified successfully <br>";
            }else{
                echo "Modification failed<br>";
            }
        }
    }
    //close the connection
    $close = mysqli_close($connect);
    if(!$close){
        die("Failed to close the database");
    }else{
        echo "Close successfully";
    }

?>

 

 

 

 

 

 

 

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