PHP while循环行数

【问题标题】：PHP while loop number of rowsPHP while循环行数
【发布时间】：2016-04-29 10:34:59
【问题描述】：

我在 php while 循环中苦苦挣扎。目标是从数据库中获取报价并在每行显示 3 列。现在看起来，while 循环每行显示一列。我应该如何纠正这个问题？

 <?php

$servername = "localhost";
$username = "";
$password = "";
$dbname = "";


$conn = new mysqli($servername, $username, $password, $dbname);

if ($conn->connect_error) {
     die("Connection failed: " . $conn->connect_error);
} 
$row = $ip['id']; 
$row = $ip['quote'];  
$row = $ip['topic'];
$row = $ip['author'];
$nr = 0;


$sql = "SELECT * FROM quotes ORDER BY date DESC limit 10";
$result = $conn->query($sql);


if ($result->num_rows > 0) {



     while($row = $result->fetch_assoc() ) {
         $nr++;


          echo  
        "<div class='container row'>
          <div class='col s12 m6 l4 z-depth-1'>
          <div class='card-panel grey darken-4 white-text center'><h5>Citat: ". $row["id"] ."</h5></div> <pre class='flow-text black-text' wrap='soft'>" ."<p class=''>Författare: ". $row["author"] ."</p>" 
          . "<p class=''>Citat: ". $row["quote"] ."</p>" .  $row["topic"] ."</pre>

        <div class='content_wrapper'>
    <h4>Vote </h4> 

        <div class='voting_wrapper' id='". $row["id"] ."'>
            <div class='voting_btn'>
                <div class='up_button'>&nbsp;</div><span class='up_votes'>0</span>
            </div>
            <div class='voting_btn'>
                <div class='down_button'>&nbsp;</div><span class='down_votes'>0</span>
            </div>
             <br>
        </div>


        </div>
        </div>
</div>";

}
 }else {
     echo "0 results";
}

$conn->close();
?>

【问题讨论】：

  • 使用 if($nr%3 == 0) 然后添加下一行，否则创建 3 列。
  • 请使用 PHP html 友好的语法。
  • 提供你想要的html格式
  • PHP and MySQL: Number of rows returned的可能重复

标签： php html css loops


【解决方案1】：

你可以这样做：

<?php

$servername     = "localhost";
$username       = "";
$password       = "";
$dbname         = "";


$conn = new mysqli($servername, $username, $password, $dbname);

if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

//DO YOU NEED THESE VARIABLES? I DON'T SEE THEIR USE HERE... BESIDES, $row DOES NOT EXIST YET...
$row    = $ip['id'];
$row    = $ip['quote'];
$row    = $ip['topic'];
$row    = $ip['author'];
$nr     = 0;


$sql = "SELECT * FROM quotes ORDER BY date DESC limit 10";
$result = $conn->query($sql);


if ($result->num_rows > 0) {
    $output     = "";
    while($row  = $result->fetch_assoc() ) {
        $topic   = trim($row["topic"]);
        $quote   = trim($row["quote"]);
        $author  = trim($row["author"]);
        $id      = trim($row["id"]);

        $output .= injectNColumnWrapper(3, $nr, "container row", $nr);
        $output .="<div class='col s12 m6 l4 z-depth-1'>";
        $output .="<div class='card-panel grey darken-4 white-text center'>";
        $output .=" <h5>Citat: {$id}</h5>";
        $output .="</div>";
        $output .="pre class='flow-text black-text' wrap='soft'>";
        $output .="<p class='flow-text-p author'>Författare: {$author}</p>";
        $output .="<p class='flow-text-p citat'>Citat: {$quote}</p>";
        $output .="<p class='flow-text-p topic'>{$topic}</p>";
        $output .="</pre>";
        $output .="<div class='content_wrapper'>";
        $output .="<h4>Vote </h4>";
        $output .="<div class='voting_wrapper' id='vote-{$id}'>";
        $output .="<div class='voting_btn'>";
        $output .="<div class='up_button'>&nbsp;</div>";
        $output .="<span class='up_votes'>0</span>";
        $output .="</div>";
        $output .="<div class='voting_btn'>";
        $output .="<div class='down_button'>&nbsp;</div>";
        $output .="<span class='down_votes'>0</span>";
        $output .="</div>";
        $output .="<br>";
        $output .="</div>";
        $output .="</div>";
        $output .="</div>";
        $nr++;

    }
    $output    .= "</div>";
    echo $output;
}else {
    echo "0 results";
}

$conn->close();


function injectNColumnWrapper($cols_per_row, $closePoint, $cssClass="container row", $nthElem=""){
    $blockDisplay       = "";
    if( ($closePoint == 0) ){
        $blockDisplay   = "<div class='" . $cssClass . " container_nr_" . $nthElem . "'>"  . PHP_EOL;
    }else if( ($closePoint % $cols_per_row) == 0 && ($closePoint != 0) ){
        $blockDisplay   = "</div><div class='" . $cssClass . " container_nr_" . $nthElem . "'>"  . PHP_EOL;
    }
    return $blockDisplay;
}

?>

每行应该有 3 列，如下所示：

<div class="container">
    <div class="col s12 m6 l4 z-depth-1">Column 1</div>
    <div class="col s12 m6 l4 z-depth-1">Column 2</div>
    <div class="col s12 m6 l4 z-depth-1">Column 3</div>
</div>

我希望这会有所帮助...

【讨论】：

  • 谢谢！它帮助很大。
  • @Thun 您能否将问题标记为完整或至少将其标记为有帮助？它可能对其他人有益......
  • 再问一个问题。 is 在 $row["author"] 和 {$row["quote"]} 之间有很多空间。如何让它更紧凑？
  • @Thun 只需将值包装在 PHP 修剪函数中，如下所示：trim({$row["author"]}) 和 修剪({$row["quote"]})。 Trim 删除字符串之前和之后的额外空格。因此 "peace " 在运行 trim() 时会变成 "peace"
  • 太棒了！但我如何将它包装在 html 代码部分中。当我编写函数时，它只显示修剪（此处的数据）？我需要包装它 {trim({$row["author"]})} 吗？
【解决方案2】：

试试看：-

<?php

$servername = "localhost";
$username = "";
$password = "";
$dbname = "";


$conn = new mysqli($servername, $username, $password, $dbname);

if ($conn->connect_error) {
     die("Connection failed: " . $conn->connect_error);
} 
$row = $ip['id']; 
$row = $ip['quote'];  
$row = $ip['topic'];
$row = $ip['author'];
$nr = 0;


$sql = "SELECT * FROM quotes ORDER BY date DESC limit 10";
$result = $conn->query($sql);

$chngrow=0;

if ($result->num_rows > 0) {



     while($row = $result->fetch_assoc() ) {
         $nr++;

   $chngrow = $chngrow + 1;

          echo  
        "<div class='container row'>
          <div class='col s12 m6 l4 z-depth-1'>
          <div class='card-panel grey darken-4 white-text center'><h5>Citat: ". $row["id"] ."</h5></div> <pre class='flow-text black-text' wrap='soft'>" ."<p class=''>Författare: ". $row["author"] ."</p>" 
          . "<p class=''>Citat: ". $row["quote"] ."</p>" .  $row["topic"] ."</pre>

        <div class='content_wrapper'>
    <h4>Vote </h4> 

        <div class='voting_wrapper' id='". $row["id"] ."'>
            <div class='voting_btn'>
                <div class='up_button'>&nbsp;</div><span class='up_votes'>0</span>
            </div>
            <div class='voting_btn'>
                <div class='down_button'>&nbsp;</div><span class='down_votes'>0</span>
            </div>
             <br>
        </div>


        </div>
        </div>
</div>";

          $mod = ($chngrow % 3);
          echo ($mod==0) ? "<br>" : "";

}
 }else {
     echo "0 results";
}

$conn->close();
?>

【讨论】：

    【解决方案3】：

    详细说明@RuchishParikh 评论，其中已经包含解决方案的核心：

    $nr = 0;
while ($row = $result->fetch_assoc()) {
  $nr++;
  if ($nr % 3 == 0) {
    echo "<div class='container row'>\n"; # start of row
  }
  echo "<div class='col s4 m6 l4 z-depth-1'>\n"; # start of column
  echo "  ...\n";
  echo "</div>\n"; # end of column
  if ($nr % 3 == 0) {
    echo "</div>\n"; # end of row
  }
}

    【讨论】：

      【解决方案4】：

      这样试试，

      $nr =0;
while($row = $result->fetch_assoc() ) {
         $nr++;
         if(($count-1)%3==0) echo '<div class="row">';
         //Add your content units here.
         if(($count)%3==0) echo '</div>';
}

      【讨论】：

        【解决方案5】：

        为每个循环增加一个计数器变量。在循环外打开 table 标记和 tr 标记。 while 循环应该只有 td 标记。如果 count%3==0 则关闭 tr 标签并打开一个新的 tr 标签。 

        $i=0
?><table><tr><?
while(condition)
{
    $i++;
    if($i%3==0)
    {
        ?></tr><tr><?
    }

    ?><td>your data</td><?
}
?></tr></table><?

        【讨论】：

          【解决方案6】：

          你搞砸了变量。 不需要在下面声明$row：

              $row = $ip['id']; 
    $row = $ip['quote'];  
    $row = $ip['topic'];
    $row = $ip['author'];

          如此处所述Why shouldn't I use mysql_* functions in PHP? 不要使用 mysql_* 函数。

          您需要获取 3 行并将它们放入一个容器中。

          <?php
$servername = "localhost";
$username = "";
$password = "";
$dbname = "";

$db = new PDO("mysql:host=$servername;dbname=$dbname;charset=UTF-8", 
              $username 
              $password);
$db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$db->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);

$sql = "SELECT * FROM quotes ORDER BY date DESC limit 10";
$nr = 0;

$stmt = $db->query('SELECT * FROM table');

while($row1 = $stmt->fetch(PDO::FETCH_ASSOC)) {
   $row2 = $stmt->fetch(PDO::FETCH_ASSOC);
   $row3 = $stmt->fetch(PDO::FETCH_ASSOC);
   $rows[] = $row1;
   if ($row2) $rows[] = $row2;
   if ($row3) $rows[] = $row3;

   echo "<div class='container row'>\n"

   foreach($rows as $row) {
      $nr++;
      $id_     = $row["id"];
      $author_ = $row["author"];
      $quote_  = $row["quote"];
      $topic_  = $row["topic"];

      echo 
        "<div class='col s12 m6 l4 z-depth-1'>
         <div class='card-panel grey darken-4 white-text center'><h5>Citat:$id_ </h5></div> 
           <pre class='flow-text black-text' wrap='soft'>
              <p class=''>Författare: $author_</p> 
              <p class=''>Citat: $quote_</p>
              $topic_
           </pre>

        <div class='content_wrapper'>
           <h4>Vote </h4> 
           <div class='voting_wrapper' id='$id_'>
            <div class='voting_btn'>
                <div class='up_button'>&nbsp;</div><span class='up_votes'>0</span>
            </div>
            <div class='voting_btn'>
                <div class='down_button'>&nbsp;</div><span class='down_votes'>0</span>
            </div>
            <br />
        </div>
        </div>
        </div>";
    }

    echo "</div>\n";
    $rows = null;
}

if ($nr == 0){
   echo "0 results";
}
?>

          【讨论】：

            【解决方案7】：

            试试这个

            $i=0
?><table><tr><?
while(condition)
{
    $i++;
    if($i%3==0)
    {
        ?></tr><tr><?
    }

    ?><td>your data</td><?
}
?></tr></table><?

            【讨论】：

            • 仅代码的答案并不是非常有用，因为它们没有解释问题是什么，以及代码为什么/如何解决它。对此添加解释会有所帮助。
            • 请提供一些解释
            猜你喜欢
            • 2016-11-27
            • 1970-01-01
            • 2012-02-21
            • 1970-01-01
            • 2011-06-02
            • 2017-11-20
            • 2011-08-06
            • 1970-01-01
            • 1970-01-01
            相关资源
            最近更新 更多
            热门标签
            Java Python linux javascript Mysql C# Docker 算法 前端 SpringBoot Redis Vue spring 设计模式 .net core .net kubernetes c++ 数据库 数据结构 大数据 js 机器学习 微服务 Android Go 程序员 面试 JVM ASP.net core 云原生 人工智能 后端 PHP git CSS golang k8s Nginx Django mybatis 深度学习 多线程 React 架构 devops 爬虫 云计算 Spring Boot LeetCode