在下面的代码中，工作正常，但我面临的唯一问题是，由 html2canvas 生成的文件在取消打印时被删除，这是正确的，但当我使用 Microsoft Print To PDF 打印机成功保存 PDF 文件时，它成功了保存文件但它执行删除文件也不知道为什么以及如何。请帮忙。
无论哪种方式，回应都是：
Response from server:
success
Deleted generated image:
success
下面是其余代码：
$("#myButtonS").click(function () {
var staffno = "<?php echo $staffno; ?>";
var container = $("#canvasSaveder");
var charA = $("#charA");
var horizontalPadding = (container.width() - charA.width()) / 2;
var verticalMargin = (container.height() - charA.height()) / 2;
charA.css({
"color": "black !important",
"font-weight": "bold",
"right": "0",
"left": "0"
});
var userCancelledPrint = false; // Define the flag here
html2canvas(container, {
scale: 2,
onrendered: function (canvas) {
var imgsrc = canvas.toDataURL("image/jpeg", 1);
$("#newimg").attr('src', imgsrc);
var dataURL = canvas.toDataURL();
$.ajax({
type: "POST",
url: "save_printed_id.php",
data: {
imgBase64: dataURL,
staffid: staffno
}
}).done(function (o) {
console.log('saved');
printImage(imgsrc);
});
}
});
function printImage(imgSrc) {
var staffno = "<?php echo $staffno; ?>";
var printWindow = window.open('', '', 'width=600,height=600');
printWindow.document.open();
printWindow.document.write('<html><body>');
printWindow.document.write('<div class="pagerA">');
printWindow.document.write('<img style="margin-top: -8px; margin-left: -8px;" src="' + imgSrc + '" width="105%" />');
printWindow.document.write('</div>');
printWindow.document.write('<div class="pagerA">');
printWindow.document.write('<img src="../../../images/idBacks.jpg" width="100%" />');
printWindow.document.write('</div>');
printWindow.document.write('</body></html>');
printWindow.document.close();
// Attach an event handler to the print window's beforeunload event
printWindow.onbeforeunload = function () {
// Set the userCancelledPrint flag to true when the print window is closed
userCancelledPrint = true;
};
printWindow.print();
// Close the print window automatically after a delay (e.g., 5 seconds)
setTimeout(function () {
printWindow.close();
// Check if the user canceled the print job and delete the image if needed
if (userCancelledPrint) {
deleteGeneratedImage();
}
}, 1000); // Adjust the delay as needed
function deleteGeneratedImage() {
// Implement code to delete the generated image here
// For example, you can make an AJAX request to a PHP script that handles the deletion.
// Ensure you have the necessary logic in place to identify and delete the correct image.
// Replace the following with your actual delete logic:
$.ajax({
type: "POST",
url: "save_printed_id_cancelled.php",
data: {
staffid: staffno
}
}).done(function (response) {
console.log('Response from server: ' + response);
if (response.trim() === "success") {
console.log('Deleted generated image: ' + response);
} else {
console.log('Failed to delete generated image: ' + response);
}
});
}
}
});
save_printed_id_cancelled.php
<?php
include ('inc/db.php');
$staffno = mysqli_real_escape_string($dba_si, $_POST['staffid']);
$sqlIM13 = "select id, filename from id_photos
where staffno = '$staffno'
order by id desc
";
$sqlIM14 = $dba_si->query($sqlIM13);
$sqlIM15 = $sqlIM14->fetch_assoc();
$fileItem5 = 'images/employees/empcards/'.$staffno.'/'.$sqlIM15['filename'];
//echo $fileItem6 = 'images/employees/empcards/'.$staffno.'/'.$sqlIM15['filename']; // Echo before any deletions
if (unlink($fileItem5)){
$dba_si->query("delete from id_photos where id = '".$sqlIM15['id']."' ");
echo "success";
// Log a message to a file
error_log("Image deleted successfully for staffno: " . $staffno);
}else{
echo "Failed to delete generated image: Error - " . error_get_last()['message'];
// Log an error message to a file
error_log("Failed to delete image for staffno: " . $staffno);
}
?>
您面临的问题似乎与生成文件的删除顺序有关。根据您的代码实现，当用户取消打印操作以及打印窗口在 1 秒延迟后自动关闭时，文件似乎都被删除。
删除 printImage() 函数内对 deleteGenerateImage() 的调用，因为在这种情况下不应删除文件：
// Remove this part inside the printImage() function
setTimeout(function () {
printWindow.close();
// Check if the user cancelled the print job and delete the image if needed
if (userCancelledPrint) {
deleteGeneratedImage();
}
}, 1000); // Adjust the delay as needed
在deleteGenerateImage()函数内，添加一个检查以确定是否应删除或保留文件。此检查应基于 userCancelledPrint 变量。如果用户取消，文件将被删除：
function deleteGeneratedImage() {
// Check if the user cancelled the print job
if (userCancelledPrint) {
// Implement the logic to delete the generated file here
// For example, you can make an AJAX request to a PHP server to handle the deletion
$.ajax({
type: "POST",
url: "save_printed_id_cancelled.php",
data: {
staffid: staffno
}
}).done(function (response) {
console.log('Response from server: ' + response);
if (response.trim() === "success") {
console.log('Deleted generated image: ' + response);
} else {
console.log('Failed to delete generated image: ' + response);
}
});
}
}
通过这些更改，只有当用户取消打印操作时，生成的文件才会被删除。如果用户使用“Microsoft Print To PDF”成功完成打印操作，则生成的文件将不会被删除。希望这可以帮助你让它发挥作用