php 检查特定输入文件是否为空
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Check if specific input file is empty
提问by Sasha
In my form I have 3 input fields for file upload:
在我的表单中，我有 3 个用于文件上传的输入字段：
<input type=file name="cover_image">
<input type=file name="image1">
<input type=file name="image2">
How can I check if cover_imageis empty - no file is put for upload?
如何检查是否cover_image为空 - 没有文件可供上传？
回答by Rudi Visser
You can check by using the sizefield on the $_FILESarray like so:
您可以使用数组size上的字段进行检查，$_FILES如下所示：
if ($_FILES['cover_image']['size'] == 0 && $_FILES['cover_image']['error'] == 0)
{
// cover_image is empty (and not an error)
}
(I also check errorhere because it may be 0if something went wrong. I wouldn't use namefor this check since that can be overridden)
（我也在error这里检查，因为这可能是因为出现0问题。我不会name用于此检查，因为它可以被覆盖）
回答by Techie
Method 1
方法一
if($_FILES['cover_image']['name'] == "") {
// No file was selected for upload, your (re)action goes here
}
Method 2
方法二
if($_FILES['cover_image']['size'] == 0) {
// No file was selected for upload, your (re)action goes here
}
回答by BenM
You can check if there is a value, and if the image is valid by doing the following:
您可以通过执行以下操作来检查是否有值，以及图像是否有效：
if(empty($_FILES['cover_image']['tmp_name']) || !is_uploaded_file($_FILES['cover_image']['tmp_name']))
{
// Handle no image here...
}
回答by Rakesh Sharma
if (empty($_FILES['cover_image']['name']))
回答by Bruno Ribeiro
simple :
简单的 ：
if($_FILES['cover_image']['error'] > 0)
// cover_image is empty
回答by Johny
if( ($_POST) && (!empty($_POST['cover_image'])) ) //verifies if post exists and cover_image is not empty
{
//execute whatever code you want
}
回答by user7282
check after the form is posted the following
在表格发布后检查以下内容
$_FILES["cover_image"]["size"]==0
回答by Prabhagaran
if($_FILES['img_name']['name']!=""){
echo "File Present";
}else{
echo "Empty file";
}
回答by Parth Dhorda
if ($_FILES['cover_image']['size'] == 0 && $_FILES['cover_image']['error'] == 0)
{
// Code comes here
}
This thing works for me........
这东西对我有用......
