PHP形式 难以捉摸的 _POST 美元的问题

嘿伙计们，这可能非常简单，我只是错过了一步。

所以我有一个表单，我想确保在移动到处理我的值并将其发送到我的电子邮件的下一页之前添加所有值。如果有人不添加值，我也有错误消息。错误消息显示在重新加载页面时。

我遇到的问题是您必须重新加载超全局帖子的页面以包含任何值。由于某种原因，在重新加载页面之前，它不会添加它们。因此，如果您填写所有 5 个输入字段，则必须重新加载页面，然后再次提交以将其发送到我的send_form_email.php脚本，因为此时已添加值。如果任何值为空，我希望它在逻辑上重新加载(这将显示错误消息，告诉用户输入字段必须包含内容(，并自动将用户发送到send_form_email.php是否已正确添加所有值。

它几乎拔掉了我的头发，所以如果有人能帮助我了解我错过了哪一块拼图，我将不胜感激！

<form name="contactform" method="post" action="<?php echo $value; ?>">
<table width="450px">
<tr>
 <td valign="top">

 </td>
 <td valign="top">
  <input  class="inputs" placeholder="firstname" type="text" name="first_name" maxlength="50" size="30" placeholder="name"><br>
 <span class="error">* <?php echo $firstErr;?></span>
 </td>
</tr>
<tr>
 <td valign="top">

 </td>
 <td valign="top">
  <input  class="inputs" placeholder="lastname" type="text" name="last_name" maxlength="50" size="30">
 <span class="error">* <?php echo $lastErr;?></span>
 </td>
</tr>
<tr>
 <td valign="top">

 </td>
 <td valign="top">
  <input class="inputs" placeholder="email" type="text" name="email" maxlength="80" size="30">
 <span class="error">* <?php echo $emailErr;?></span>
 </td>
</tr>
<tr>
 <td valign="top">

 </td>
 <td valign="top">
  <input  class="inputs" placeholder="telephone" type="text" name="telephone" maxlength="30" size="30">
 <span class="error">* <?php echo $telephoneErr;?></span>
 </td>
</tr>
<tr>
 <td valign="top">

 </td>
 <td valign="top">
  <textarea  class="inputs" placeholder="comments" name="comments" maxlength="1000" cols="25" rows="6"></textarea>
 <span class="error">* <?php echo $commentsErr;?></span>
 </td>
</tr>
<tr>
 <td colspan="2" style="text-align:center">
   <input type="submit" value="Submit" style="background-color: #0F6D87;
    font-family: Exo-Light;
    color: #000000;
    width: 75px;
    font-weight: bold;
    border-color: #003D69;
    border-style: outset;
    font-size: .8em;
    box-shadow: 2px 2px 2px rgba(0, 34, 97, 0.6);">
  <INPUT TYPE="RESET">
 </td>
</tr>
</table>
</form>


<?php
if ($_SERVER["REQUEST_METHOD"] == "POST"){
    if (!empty($_POST["first_name"]) && !empty($_POST["last_name"]) && !empty($_POST["email"])  &&  !empty($_POST["telephone"]) && !empty($_POST["comments"])) {
  $value ="http://cdubach.com/inc/send_form_email.php";
    } elseif  (empty($_POST["first_name"]) || empty($_POST["last_name"]) || empty($_POST["email"]) || empty($_POST["telephone"]) || empty($_POST["comments"])){

        $value = "#";
    }

}

    $first_name = $_POST['first_name']; // required
    $last_name = $_POST['last_name']; // required
    $email_from = $_POST['email']; // required
    $telephone = $_POST['telephone']; // not required
    $comments = $_POST['comments']; // required

echo $_POST['submit'] . " = Submit <br>";
echo $_POST["first_name"] . " =  First Name  <br>"; 
echo $_POST["last_name"] . " = Last Name  <br>"; 
echo $_POST["email"] . "= Email  <br>"; 
echo $_POST["telephone"] . "= Telephone  <br>"; 

echo $_POST["comments"] . "= Comments <br>"; 
echo var_dump($_Post) . "= Dump <br>";                                               
 echo $value . " = Value <br>" ;                                          

echo  $_SERVER["PHP_SELF"];
header('Content-Type: text/plain');
var_dump(htmlspecialchars("<a href='test'>Test</a>", ENT_QUOTES, 'UTF-8'));
echo "<br>";
echo htmlspecialchars("<a href='test'>Test</a>", ENT_XHTML, 'UTF-8');
echo "<br>";
$str = "A 'quote' is <b>bold</b>";
/* */
//convert from utf8
 $str = utf8_decode($str);
 //translate HMTL entities
 $trans = get_html_translation_table(HTML_ENTITIES);
$str = strtr($str, $trans);
echo htmlspecialchars($str);
echo "<br>";
echo htmlentities($str, ENT_QUOTES);
$new = htmlspecialchars("<a href='test'>Test</a>", ENT_QUOTES);
echo $new; // &lt;a href=&#039;test&#039;&gt;Test&lt;/a&gt;

if ($_SERVER["REQUEST_METHOD"] == "POST") {
     //Check First Name Field if Nothing Post Error
  if (empty($_POST["first_name"])) {
    $firstErr = "Name is required";
  } else {
    $firstErr = test_input($_POST["name"]);
  }

    //Check Last Name Field if Nothing Post Error
    if (empty($_POST["last_name"])) {
    $lastErr = "Last Name is required";
  } else {
    $lastErr = test_input($_POST["last_name"]);
  }

 //Check Email Field if Nothing Post Error
  if (empty($_POST["email"])) {
    $emailErr = "Email is required";
  } else {
    $emailErr = test_input($_POST["email"]);
  }

 //Check Telephone Field if Nothing Post Error
  if (empty($_POST["telephone"])) {
    $telephoneErr = "Telephone is Required";
  } else {
    $telephoneErr = test_input($_POST["telephone"]);
  }
     //Check Comments Field if Nothing Post Error 
  if (empty($_POST["comments"])) {
    $commentsErr = "Comments is Required";
  } else {
    $commentsErr = test_input($_POST["comments"]);
  }

    //Check Comments
}
function test_input($data) {
   $data = trim($data);
   $data = stripslashes($data);
   $data = htmlspecialchars($data);
   return $data;
}
?>