Question

每当我刷新页面或离开并返回时，图像都会从站点和数据库中消失。我不希望表单重定向到另一个页面，我只是希望它保持在同一页面上，但只在按下提交按钮时运行查询。

<?php
$display = mysql_query("SELECT image FROM `blog_users` WHERE username = '$session->username'");
$res = mysql_fetch_array($display); echo "<image style='height: 50px; width:50px;' src='".$res['image']."'>";
$close = 0;
?>

//the above code displays the image

<?php
 define ("MAX_SIZE","1000"); 

//This function reads the extension of the file. It is used to determine if the
// file  is an image by checking the extension.
 function getExtension($str) {
         $i = strrpos($str,".");
         if (!$i) { return ""; }
         $l = strlen($str) - $i;
         $ext = substr($str,$i+1,$l);
         return $ext;
 }

//This variable is used as a flag. The value is initialized with 0 (meaning no 
// error  found)  
//and it will be changed to 1 if an errro occures.  
//If the error occures the file will not be uploaded.
 $errors=0;
//checks if the form has been submitted
 if(isset($_POST['Submit'])) 
 {
    //reads the name of the file the user submitted for uploading
    $image=$_FILES['image']['name'];
    //if it is not empty
    if ($image) 
    {
    //get the original name of the file from the clients machine
        $filename = stripslashes($_FILES['image']['name']);
    //get the extension of the file in a lower case format
        $extension = getExtension($filename);
        $extension = strtolower($extension);
    //if it is not a known extension, we will suppose it is an error and 
        // will not  upload the file,  
    //otherwise we will do more tests
 if (($extension != "jpg") && ($extension != "jpeg") && ($extension !=
 "png") && ($extension != "gif")) 
        {
        //print error message
            echo '<h3>Unknown extension!</h3>';
            $errors=1;
        }
        else
        {
//get the size of the image in bytes
 //$_FILES['image']['tmp_name'] is the temporary filename of the file
 //in which the uploaded file was stored on the server
 $size=filesize($_FILES['image']['tmp_name']);

//compare the size with the maxim size we defined and print error if bigger
if ($size > MAX_SIZE*1024)
{
    echo '<h1>You have exceeded the size limit!</h1>';
    $errors=1;
}

//we will give an unique name, for example the time in unix time format
$image_name=time().'.'.$extension;
//the new name will be containing the full path where will be stored (images 
//folder)
$newname="upload/".$image_name;
//we verify if the image has been uploaded, and print error instead
$copied = copy($_FILES['image']['tmp_name'], $newname);
if (!$copied) 
{
    echo '<h3>Copy unsuccessfull!</h3>';

    $errors=1;
}}}}
//this code sends the image location to the database
mysql_query("UPDATE blog_users SET image = '$newname' WHERE username = '$session->username'") ; 
if( strcasecmp($_SERVER['REQUEST_METHOD'],"POST") === 0) {
  $_SESSION['postdata'] = $_POST;
  header("Location: ".$_SERVER['PHP_SELF']."?".$_SERVER['QUERY_STRING']);
  exit;

}

 ?>

<form name="newad" method="post" enctype="multipart/form-data"  
action=""><img src="" alt="" />
<head>
    <script type="text/javascript" src="http://code.jquery.com/jquery-2.0.0.js"></script>
   <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> 


            <script type="text/javascript">
                $(document).ready(
        function(){
            $('input:submit').attr('disabled',true);
            $('input:file').change(
                function(){
                    if ($(this).val()){
                        $('input:submit').removeAttr('disabled'); 
                    }
                    else {
                        $('input:submit').attr('disabled',true);
                    }
                });
        });
            </script>
    </head>
 <table>
    <tr><td><input type="file" name="image" id="file"></td></tr>
    <tr><td><input name="Submit" type="submit" value="Upload image" id="image_upload" disabled>
       </td></tr>
 </table>   
 </form>

Answer 1

回答问题的评论。

if(isset($_POST['Submit'])){...} - ... =要执行的代码。

现在的方式是mysql_query("UPDATE...无论如何都会运行。

换句话说，为它重新定位支撑。

您有}}}}

删除其中一个大括号并将其重新定位在?>标记之前，您应该好好去。

if(isset($_POST['Submit'])){
...

$errors=1;
}}}
//this code sends the image location to the database
mysql_query("UPDATE blog_users SET image = '$newname' WHERE username = '$session->username'") ; 
if( strcasecmp($_SERVER['REQUEST_METHOD'],"POST") === 0) {
  $_SESSION['postdata'] = $_POST;
  header("Location: ".$_SERVER['PHP_SELF']."?".$_SERVER['QUERY_STRING']);
  exit;

    }

} // brace for if(isset($_POST['Submit']))

?>

每当我刷新代码时，查询都会重新加载并向数据库发送空白信息？

1 个答案: