本文介绍了如何安全地检查节点是否为空?(Symfony 2 爬虫)的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
当我尝试从页面中获取一些不存在的内容时,我发现了这个错误:
When I try to take some nonexistent content from page I catch this error:
The current node list is empty.
500 Internal Server Error - InvalidArgumentException
如何安全地检查此内容是否存在?这里有一些不起作用的例子:
How can I safely check exists this content or not? Here some examples that does not work:
if($crawler->filter('.PropertyBody')->eq(2)->text()){
// bla bla
}
if(!empty($crawler->filter('.PropertyBody')->eq(2)->text())){
// bla bla
}
if(($crawler->filter('.PropertyBody')->eq(2)->text()) != null){
// bla bla
}
谢谢,我帮助了自己:
$count = $crawler->filter('.PropertyBody')->count();
if($count > 2){
$marks = $crawler->filter('.PropertyBody')->eq(2)->text();
}
推荐答案
你有没有尝试过这样的事情?
Have you tried something like this?
$text = null;
if (!empty($body = $crawler->filter('.PropertyBody'))) {
if (!empty($node = $body->eq(2))) {
$text = $node->text();
}
}
$this->assertContains('yourText', $text);
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