javascript - Php/Javascript 未捕获语法错误 : Unexpected identifier

Question

我已经多次检查我的代码，但它似乎无法正常工作，因为当 PHP 运行时，它只是在浏览器控制台中显示以下错误:

Uncaught SyntaxError: Unexpected identifier.

我不确定这只是一个简单的问题还是有更多问题。

    <div class="alert alert-success" role="alert"><h4 id="Txt"> Now In Development</h4></div>
    <form method="POST" action="#goHere">
        <input type="email" name="email" placeholder="Enter Email For Updates">
        <input type="submit" name="submit">
    </form>

if(isset($_POST['submit'])) {
     $email = htmlentities(strip_tags($_POST['email']));

     $logname = 'list/email.txt';
     $logcontents = file_get_contents($logname);
     $searchfor = $email;

     // the following line prevents the browser from parsing this as HTML.
     //header('Content-Type: text/plain');

     // get the file contents, assuming the file to be readable (and exist)
     $contents = file_get_contents($logname);
     // escape special characters in the query
     $pattern = preg_quote($searchfor, '/');
     // finalise the regular expression, matching the whole line
     $pattern = "/^.*$pattern.*\$/m";
     // search, and store all matching occurences in $matches
     $filecontents = $email."\r\n";
     $fileopen = fopen($logname,'a+');
     $filewrite = fwrite($fileopen,$filecontents);
     $fileclose = fclose($fileopen);
     if($email == NULL) {
       echo '<Script> document.getElementById("Txt").innerHTML = "<div      class="alert alert-danger" role="alert">"You entered Nothing</div>"; </script>';
     } elseif(preg_match_all($pattern, $contents, $matches)){
       echo '<Script> document.getElementById("Txt").innerHTML = "<div      class="alert alert-success" role="alert">Email was already added</div>"; </script>';
} else {
    if(!$fileopen or !$filewrite or !$fileclose) {
      echo '<Script> document.getElementById("Txt").innerHTML = "Thankyou"; </script>';
    } else {
        echo '<Script> document.getElementById("Txt").innerHTML = "<div class="alert alert-success" role="alert">Email Succefully Added"; </script>';
    }
  }   
}

Answer 1

问题

问题出在脚本标签字符串上。

如果您检查输出的 <script>标记，您可能会看到类似这样的内容:

<script> document.getElementById("Txt").innerHTML = "<div      class="alert alert-success" role="alert">Email was already added</div>"; </script>

请注意，双引号不会在 HTML 中转义。

可能的解决方案

解决这个问题的一种方法是转义 HTML 中的双引号:

echo '<Script> document.getElementById("Txt").innerHTML = "<div      class=\"alert alert-success\" role=\"alert\">Email was already added</div>"; </script>';

或者使用转义单引号分隔 HTML:

echo '<Script> document.getElementById("Txt").innerHTML = \'<div      class="alert alert-success" role="alert">Email was already added</div>\'; </script>';

其他选项包括 heredoc或者可能nowdoc格式或模板引擎。

请参阅 this phpfiddle 中的转义单引号定界符方法的演示。 .