如何让我的php表单正常工作？

Question

我使用php为我的网站构建了一个表单。表单提交后，内容将通过电子邮件发送给我，并将用户重定向到其他页面。当我完全填写表格时，代码正常工作。但是，其中一个字段是文件上传，当我没有上传任何内容时，表单仍会发送，但会导致500个内部服务器错误页面。我怎样才能做到这一点，所以当文件没有上传时，表单仍然会重定向到正确的页面？我下面包括

<?php 
$email_to = "[email protected]"; 
$email_subject = "Completed Questionnaire"; 
$name = $_POST['name']; 
$gradyear = $_POST['gradyear']; 
$hschool = $_POST['hschool']; 
$hometown = $_POST['hometown']; 
$email_from = $_POST['email']; 
$DOB = $_POST['DOB']; 
$GPA = $_POST['GPA']; 
$height = $_POST['height']; 
$weight = $_POST['weight']; 
$about = $_POST['about']; 

$message = "Form details below.\n\n"; 
function clean_string($string) { 
$bad = array("content-type","bcc:","to:","cc:","href"); 
return str_replace($bad,"",$string);} 

$message .= "Name: ".clean_string($name)."\n"; 
$message .= "Graduation Year: ".clean_string($gradyear)."\n"; 
$message .= "High School: ".clean_string($hschool)."\n"; 
$message .= "Hometown: ".clean_string($hometown)."\n"; 
$message .= "Email: ".clean_string($email_from)."\n"; 
$message .= "Date of Birth: ".clean_string($DOB)."\n"; 
$message .= "GPA: ".clean_string($GPA)."\n"; 
$message .= "Height: ".clean_string($height)."\n"; 
$message .= "Weight: ".clean_string($weight)."\n"; 
$message .= "About: ".clean_string($about)."\n"; 


/* GET File Variables */ 
$tmpName = $_FILES['attachment']['tmp_name']; 
$fileType = $_FILES['attachment']['type']; 
$fileName = $_FILES['attachment']['name']; 

/* Start of headers */ 
$headers = "From: $email_from"; 

if (file($tmpName)) { 
/* Reading file ('rb' = read binary) */ 
$file = fopen($tmpName,'rb'); 
$data = fread($file,filesize($tmpName)); 
fclose($file); 

/* a boundary string */ 
$randomVal = md5(time()); 
$mimeBoundary = "==Multipart_Boundary_x{$randomVal}x"; 

/* Header for File Attachment */ 
$headers .= "\nMIME-Version: 1.0\n"; 
$headers .= "Content-Type: multipart/mixed;\n" ; 
$headers .= " boundary=\"{$mimeBoundary}\""; 

/* Multipart Boundary above message */ 
$message = "This is a multi-part message in MIME format.\n\n" . 
"--{$mimeBoundary}\n" . 
"Content-Type: text/plain; charset=\"iso-8859-1\"\n" . 
"Content-Transfer-Encoding: 7bit\n\n" . 
$message . "\n\n"; 

/* Encoding file data */ 
$data = chunk_split(base64_encode($data)); 

/* Adding attchment-file to message*/ 
$message .= "--{$mimeBoundary}\n" . 
"Content-Type: {$fileType};\n" . 
" name=\"{$fileName}\"\n" . 
"Content-Transfer-Encoding: base64\n\n" . 
$data . "\n\n" . 
"--{$mimeBoundary}--\n"; 
} 

@mail($email_to, $email_subject, $message, $headers); 
header("Location: http://myURL.com/contact.html"); 

?> 

Answer 1

你应该先检查我的代码，一个文件处理文件之前确实上传：

if (! empty($_FILES)) { 
//file manipulation... 
}