PHP 上传 IF ISSET 总是说它是？
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PHP Upload IF ISSET always says it is?
提问by uollaa
OK, i have some kind of strange problem with my code. I'm trying to make uploading form with text along photos. Now, I need to check if the photo is uploaded or the text is inserted only.
好的，我的代码有一些奇怪的问题。我正在尝试制作带有照片文字的上传表单。现在，我需要检查照片是否已上传或仅插入文本。
The simplified code looks like this:
简化后的代码如下所示：
if (isset ($_FILES['image'])){
echo 'yes';
} else {
echo 'no';
}
the form looks like:
表格看起来像：
<form action="" method="post" enctype="multipart/form-data" class="contact-form">
<form action="" method="post" enctype="multipart/form-data" class="contact-form">
<label for="title"><strong>Title</strong> (required)</label>
<input type="text" name="title" value="" required>
<label><span class="small"><strong>Add a photo</strong></span></label>
<input type="file" name="image"/>
<input type="submit" name"submit" value="Submit">
</form>
Now, basically, what I'm trying to make is a check if file is attached or not, because I need an alternate option for posting posts without photos, in the same form; but, the problem is that no mather if it is attached or not it always says YES.
现在，基本上，我要做的是检查文件是否已附加，因为我需要一个替代选项来以相同的形式发布没有照片的帖子；但是，问题是，无论是否附加，它总是说是。
Help, anyone.
帮助，任何人。
回答by Jimbo
To check if the file has been uploaded, how about:
要检查文件是否已上传，请执行以下操作：
if (!file_exists($_FILES['image']['tmp_name']) || !is_uploaded_file($_FILES['image']['tmp_name']))
{
echo 'No upload';
}
else
{
// Your file has been uploaded
}
is_uploaded_file()is the choice here, check the docs out for it.
is_uploaded_file()是这里的选择，请查看文档。
$_FILESis an array of files, and each file in the first dimension of the array is automatically given a ['tmp_name']key in the second dimension, with the value being it's temporary location.
$_FILES是一个文件数组，数组第一维中的每个文件都会自动['tmp_name']在第二维中给出一个键，值是它的临时位置。
Obviously you then need to use move_uploaded_file()on the temporary file.
显然，您需要move_uploaded_file()在临时文件上使用。
回答by bystwn22
You are checking only that $_FILES['image']passed from your form.
But you are not checking that posted $_FILES['image']is empty or its contains a valid file data
Read more here http://www.php.net/manual/en/features.file-upload.php
您正在检查仅从$_FILES['image']您的表单传递的内容。
但是您没有检查发布的内容$_FILES['image']是否为空或其包含有效的文件数据
在此处阅读更多信息http://www.php.net/manual/en/features.file-upload.php
<?php
if ( isset( $_FILES["image"] ) && !empty( $_FILES["image"]["name"] ) ) {
if ( is_uploaded_file( $_FILES["image"]["tmp_name"] ) && $_FILES["image"]["error"] === 0 ) {
// everything okay, do process
echo 'yes';
exit();
}
}
echo 'no';
?>
回答by Stacy Davidson
The reason "isset" doesn't work is most likely because $_FILES is considered set even when it is set to "null". I found the empty() suggestion to be the cleanest. Although, unless you're using a large form with multiple files, I would remove the brackets entirely.
“isset”不起作用的原因很可能是因为即使将 $_FILES 设置为“null”，也认为它已设置。我发现 empty() 建议是最干净的。虽然，除非您使用包含多个文件的大型表单，否则我会完全删除括号。
if (empty ($_FILES)){
echo 'No file';
} else {
echo 'File found';
}
回答by Drew Lemmy
Use empty() instead.
使用 empty() 代替。
if (!empty ($_FILES['image'])){
echo 'yes';
} else {
echo 'no';
}
