Question

我是一名在php项目中工作的新手。我想在html选项标签中添加一个php代码。这就是我正在做的......

$companies = Company::find('all');
foreach ($companies as $c)
{
  echo "<option value='".$c->id."' ".if($c->id == $companyselected){'selected'}.">".$c->name."</option>" ;
}

$companyselected是我从控制器传递的变量，它包含应该在下拉列表顶部显示的公司ID。它什么也没输出。为什么我不能这样添加。这是正确的添加这样的。我很长时间坚持这个。请帮帮我们

Answer 1

试试这个：

echo "<option value='".$c->id."' ".(($c->id == $companyselected) ? 'selected=selected':'').">".$c->name."</option>" ;

<强> EDITED

$str = "<option value='".$c->id."' ";
$str .= (($c->id == $companyselected) ? "selected='selected'":"");
$str .= ">".$c->name."</option>" ;
echo $str;

Answer 2

试试这个，你不能在echo中使用if语句。

$companies = Company::find('all');
foreach ($companies as $c)
{
    if($c->id == $companyselected) {
        echo "<option value='".$c->id."' selected='selected'>".$c->name."</option>" ;
    } else {
        echo "<option value='".$c->id."'>".$c->name."</option>" ;
    }
}

或者

foreach ($companies as $c)
{
   $selected = ($c->id == $companyselected) ? 'selected' : '';
   echo "<option value='".$c->id."' ".$selected.">".$c->name."</option>" ;
}

Answer 3

你应该这样做：

使用ternary operator

foreach ($companies as $c)
  {
   $selected = ($c->id == $companyselected) ? "selected='selected'" : "";
   echo "<option value='".$c->id."' ".$selected.">".$c->name."</option>" ;
  }

Answer 4

这是写这种方式。

$companies = Company::find('all');
foreach ($companies as $c)
{
         echo "<option value='".$c->id."' ";
         if($c->id == $companyselected){
              echo 'selected';
         }
         echo ">".$c->name."</option>" ;
}

Answer 5

使用此

$companies = Company::find('all');

$selected= '';

foreach ($companies as $c)
{
    if($c->id == $companyselected){
        $selected='selected';
    }
    echo "<option value='".$c->id."' ".$selected." >".$c->name."</option>" ;
}

为什么我不能在选项标签中添加PHP代码？

5 个答案: