图片重新选择php

Question

我有一张桌子，每一行都有一个图像和一些文本。 当前，当我在不选择图像的情况下更新内容时，图像的数据库字段将被清除。 但是，如果没有选择图像，我想保留旧图像。

我该怎么做？

需要注意的是，我知道不推荐使用mysql_ *函数。

<?php

include("db/db.php");

$select_db = "select * from aboutus WHERE id=1";
$run_news = mysql_query($select_db);

while ($row = mysql_fetch_array($run_news)) {
    $id = $row['id'];
    $image = $row['image'];
    $content = $row['content'];
}
?>
<div class="box box-primary">
    <div class="box-header with-border">
        <h3 class="box-title">Update About Content</h3>
    </div>
    <!-- /.box-header -->
    <!-- form start -->
    <form role="form" method="post" action="aboutcontent.php?id=1"  enctype="multipart/form-data">
        <div class="box-body">

            <div class="form-group">
                <label for="exampleInputFile">Reselect Image *(H=530px, W=800px)</label>
                <input type="file" name="user_image"  id="exampleInputFile">
            </div>

            <div class="form-group">
                <label >Content</label><br>
                <textarea name="content" class="tinymce" class="form-control" rows="15"><?php echo $content; ?></textarea>
            </div>
        </div>
        <!-- /.box-body -->

        <div class="box-footer">
            <button type="submit" name="update" class="btn btn-primary">Update</button>
        </div>
    </form>
</div>

<?php

include("db/db.php");

// Code for UPDATE button
if (isset($_POST['update'])) {

    $content = $_POST['content'];

    $imgFile = $_FILES['user_image']['name'];
    $tmp_dir = $_FILES['user_image']['tmp_name'];
    $imgSize = $_FILES['user_image']['size'];

    if ($imgFile) {
        $upload_dir = 'images/about/'; // upload directory  
        $imgExt = strtolower(pathinfo($imgFile, PATHINFO_EXTENSION)); // get image extension
        $valid_extensions = array('jpeg', 'jpg', 'png', 'gif'); // valid extensions
        $userpic = rand(1000, 1000000) . "." . $imgExt;

        if (in_array($imgExt, $valid_extensions)) {
            if ($imgSize < 5000000) {
                unlink($upload_dir . $row['image']);
                move_uploaded_file($tmp_dir, $upload_dir . $userpic);
            }
            else {
                $errMSG = "Sorry, your file is too large it should be less then 5MB";
            }
        }
        else {
            $errMSG = "Sorry, only JPG, JPEG, PNG & GIF files are allowed.";
        }
    }
    else {
        // if no image selected the old image remain as it is.
        $userpic = $row['image']; // old image from database
    }

    // if no error occured, continue ....
    $sql = "UPDATE aboutus SET image='$userpic', content='$content' WHERE id=1";
    $query = mysql_query($sql);
    if (!$query) {
        die('Invalid query: ' . mysql_error());
    }
    else {
        echo "<script>alert('Successfully Updated!!!'); window.location='index.php?aboutcontent'</script>";
    }
}

?>

Answer 1

既然我还不能发表评论，那么当您提交的图像中没有图像时，您将进入if或else语句（在每个部分中放置一个die（某些内容））以弄清楚这一点。 如果您没有做到这一点，请尝试：

//initialize error message
$errMSG = '';

//this error means 'There is no error, the file uploaded with success'
if($_FILES['user_image']['error'] == 0){
 //rest of logic to get the filename and move files stuff
}
else{
   $userpic = $row['image'];
}

//you dont want to update database if there are errors
if(errMSG = ''{
  $sql = "UPDATE aboutus SET image='$userpic', content='$content' WHERE id=1";
}

或仅进行两个不同的数据库调用，一个用于拥有图像时，而另一个用于不具有图像时

if($_FILES['user_image']['error'] == 0){
 //rest of logic to get the filename and move files stuff
    //if everything else is true (has filename and correct file size)

   //you dont want to update database if there are errors
   if(errMSG = ''{
      $sql = "UPDATE aboutus SET image='$userpic', content='$content' WHERE id=1";
}
  $sql = "UPDATE aboutus SET image='$userpic', content='$content' WHERE id=1";
}
else{
   $userpic = $row['image'];

  $sql = "UPDATE aboutus SET content='$content' WHERE id=1";
}

http://php.net/manual/zh/features.file-upload.errors.php

Answer 2

通过检查文件是否已提交，可以轻松解决该问题：

if(!empty($userpic)){
    // SQL update here
} else {
    // No file submitted so don't update
}

之所以获得空的mysql字段，是因为您正在使用一个空的变量更新该字段。