Php 为什么我会有这些错误?

Php 为什么我会有这些错误?,php,Php,在两页中,我有一个问题。第一个问题是在提交之前,我收到此警报: (注意:未定义索引:在第15行的C:\xampp\htdocs\art-legend\12\admin\add.php中提交) 本页第15行是 (if ($_POST['submit'] && !empty($_FILES)){) 第二个问题是,在我放任何他们放的图片之前,我在上面有一个图片,但我仍然没有放任何图片,我有这张图片 第三个错误是当我上传一个图像时,我看不到它,我有一个和上一个屏幕一样的屏幕 <!

在两页中,我有一个问题。第一个问题是在提交之前,我收到此警报:

(注意:未定义索引:在第15行的C:\xampp\htdocs\art-legend\12\admin\add.php中提交)

本页第15行是

(if ($_POST['submit'] && !empty($_FILES)){)
第二个问题是,在我放任何他们放的图片之前,我在上面有一个图片,但我仍然没有放任何图片,我有这张图片

第三个错误是当我上传一个图像时,我看不到它,我有一个和上一个屏幕一样的屏幕

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=windows-1256" />
<title>Untitled Document</title>
<title>Untitled Document</title>
</head>

<body>
<?
if ($_POST['submit'] && !empty($_FILES)){

    $formok = TRUE;

    $title = $_POST['title'];
    $thread = $_POST['elm1'];
    $date =  date("d/m/y h;i:s");

   $path = $_FILES['upload']['tmp_name'];
   $name = $_FILES['upload']['name'];
   $size = $_FILES['upload']['size'];
   $type = $_FILES['upload']['type']; 
   $error = $_FILES['upload']['error'];

    if (!is_uploaded_file($path)){
        $formok = FALSE; 
        echo "there is no file uploaded try again";

        }

        if (!in_array($type,array('image/png','image/jpg','image/jpeg'))){
            $formok = FALSE ;
            echo "the file is not image try again ";
            }

        if (filesize($path)>800000){
            $formok = FALSE ;
            echo "the file is bigger ";
            }

        if ($formok){
            if ($connect = mysqli_connect('localhost','root','adminpass','flip')){
                $content = file_get_contents($path);
                $safetitle = mysqli_real_escape_string($connect,$title);
                $safethread = mysqli_real_escape_string($connect,$thread);
                $safeimage = mysqli_real_escape_string($connect,$thread);


                $sqltitle ="insert into title(title) values ('$safetitle')";
                $sqlthread = "insert into threads (topic,date) values ('$safethread','$date')";
                $sqlimge ="insert into images (name,size,type,content) values ('$name','$size','$type','$safeimage')";

                $querytitle = mysqli_query($connect,$sqltitle);
                $querythread = mysqli_query($connect,$sqlthread);
                $queryimage = mysqli_query($connect,$sqlimge);


                if ($querytitle && $querythread && $queryimage){

                    $imageid = mysqli_insert_id($connect);
                    }

                    mysqli_close($connect);

                }
                else {
                    echo "There is error in database connect";
                    }

                    echo "insert done all ";
            }
    }
?>

<img src="image.php?id=<?=$imageid; ?>" />
<hr />

<form action="<?php echo $_SERVER["PHP_SELF"];?>" method="post" enctype="multipart/form-data">
<p>
title :
<input type="text" name="title" />
</p>
<div>
    <textarea id="elm1" name="elm1" rows="15" cols="80" style="width: 80%">

    </textarea>
</div>
<input type="hidden" name="MAX_FILE_SIZE" value="800000" />
<p>
<input type="file" name="upload" />
</p>
<p>
<input type="submit" name="submit" value="process" />
</p>
</form>

</body>
</html>

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无标题文件
使用

isset-确定变量是否已设置且不为空


如果(isset($\u POST['submit'])&&!empty($\u FILES)){
将这一行添加到代码的最顶端,这应该可以解决
如果(isset($\u POST['submit']),那么这第一个问题现在可以解决了。谢谢。另外一个问题呢?你可以在image.php中发布代码吗?
<?

$imageid = $_GET['id'];

if ( mysqli_connect('localhost','root','adminpass','flip')){

    $escape = mysqli_real_escape_string($connect,$content);
    $sql = "select type,content from images where id =$imageid";
    $query = mysqli_query($connect, $sql);


    $fetch = mysqli_fetch_array($query,MYSQLI_ASSOC);
    mysqli_free_result($query);
    mysqli_close($connect);

    }

        else {
            echo"ther is no connection 2";
            }


if (!empty($fetch)){

    header("Content-type:{$fetch['type']}");
    echo $fetch['content'];

    }

?>
<?
if (isset($_POST['submit']) && !empty($_FILES)){