dpi9530 2013-04-12 11:30
浏览 45

检查变量是否已设置然后回显而不重复?

Is there a concise way to check if a variable is set, and then echo it without repeating the same variable name?

Instead of this:

<?php
    if(!empty($this->variable)) {
        echo '<a href="', $this->variable, '">Link</a>';
    }
?>

I'm thinking about something in the lines of this C-style pseudocode:

<?php
    echo if(!empty($this->variable, '<a href="', %s, '">Link</a>'));
?>

PHP has sprintf, but it doesn't quite do what I was hoping for. If course I could make a method/function out of it, but surely there must be a way to do it "natively"?

Update: Ternary operations would also repeat the $this->variable part, if I understood it?

echo (!empty($this->variable) ? '<a href="',$this->variable,'">Link</a> : "nothing");
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3条回答 默认 最新

  • dsdsm2016 2013-04-12 11:38
    关注

    Use isset function of php like this:

    <?php
    
      echo $result = isset($this->variable) ? $this->variable : "variable not set";
    
     ?>
    

    i think this will help.

    评论

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