Question

嘿伙计们我是php的新手。首先，我有一个循环，从xml文件中获取数据。在循环内部我想创建一个if条件，它将有一个flag = 0，当$ item ['description']第二次相同时（flag = 1）然后停止并继续另一个。任何帮助将不胜感激：D

 foreach ($item_array as $item) {
            $flag=0;
            if ( make_safe($item['diamerisma']) == $_GET['diamerisma'] ) {
              if ( $item['description'] == $item['description'] && flag == 0 ) {
            $html .= '<ul data-role="listview" id="weatherList" data-theme="b" data-insert="true" >';
            $html .= '<li><div id="Left1"><a href="main.php?description=Kiklades">' . make_safe( $item['description'] ) . '</a></div></li>';
            $html .= '</ul>';
            echo '</dd>';
            $flag=1;
              }
            }
        }
    }

这是xml代码

    <item>
        <title>Alexan</title>
        <description>Ioannina</description>
        <diamerisma>Ipeiros</diamerisma>
        <metar>1009</metar>
    </item>
    <item>
        <title>Center</title>
        <description>Ioannina</description>
        <diamerisma>Ipeiros</diamerisma>
        <metar>1010</metar>
    </item>
    <item>
        <title>Tzoumerka</title>
        <description>Ioannina</description>
        <diamerisma>Ipeiros</diamerisma>
        <metar>1011</metar>
    </item>
    <item>
        <title>Center</title>
        <description>Igoumenitsa</description>
        <diamerisma>Ipeiros</diamerisma>
        <metar>1012</metar>
    </item>
<item>
        <title>Paramithia</title>
        <description>Igoumenitsa</description>
        <diamerisma>Ipeiros</diamerisma>
        <metar>1013</metar>
    </item>
<item>
        <title>Arta</title>
        <description>Arta</description>
        <diamerisma>Ipeiros</diamerisma>
        <metar>1014</metar>
    </item>

现在代码显示Ioannina，Ioannina，Ioannina，Igoumenitsa，Igoumenitsa，Arta和我喜欢展示：Ioannina，Igoumenitsa，Arta

Answer 1

只是一些注释：你可以跳转到循环的下一个交互作为foreach键入continue，如果在foreach循环中设置$flag = 0，当你检查它时它总是0。并且总是$ item ['description']将等于$ item ['description']

我的建议是在数组中使用值：

$used_values = array();
foreach ($item_array as $item) {
    if ( make_safe($item['diamerisma']) == $_GET['diamerisma'] ) {
        if (!in_array($item['description'], $used_values) ) {//This will check if this value hasn't been listed yet
            $html .= '<ul data-role="listview" id="weatherList" data-theme="b" data-insert="true" >';
            $html .= '<li><div id="Left1"><a href="main.php?description=Kiklades">' . make_safe( $item['description'] ) . '</a></div></li>';
            $html .= '</ul>';
            $html .= '</dd>';
            $used_values[] = $item['description'];//here you preserve used values for avoiding repetition
        }
    }
}

Answer 2

    $processed=array();

    foreach ($item_array as $item) {

    if ( ! in_array( $item['diamerisma'], $processed ) ) //if diamerisma not in processed array
          {
                if ( make_safe($item['diamerisma']) == $_GET['diamerisma'] )

                {

                $html .= '<ul data-role="listview" id="weatherList" data-theme="b" data-insert="true" >';
                $html .= '<li><div id="Left1"><a href="main.php?description=Kiklades">' . make_safe( $item['description'] ) . '</a></div></li>';
                $html .= '</ul>';
                echo '</dd>'; 
                $processed[] = $item['diamerisma']; //add diamerisma to processed array

                }  

          }

        }

Answer 3

看起来你想要在循环之外启动$ flat并且当它大于1时，break退出循环。 break语句会将您从控制语句中跳出，或者更多。

$flag=0;
foreach ($item_array as $item) {
  if ( make_safe($item['diamerisma']) == $_GET['diamerisma'] ) {
    if ( $item['description'] == $item['description']) {
      $html .= '<ul data-role="listview" id="weatherList" data-theme="b" data-insert="true" >';
      $html .= '<li><div id="Left1"><a href="main.php?description=Kiklades">' . make_safe( $item['description'] ) . '</a></div></li>';
      $html .= '</ul>';
      echo '</dd>';
      $flag += 1;
    }
  }
  if ($flag > 1) {
    break;
  }
}

请参阅此处的文件：

http://php.net/break

如果flag = 0，则使用php从xml获取数据

3 个答案: