How to check if the file input field is empty?

问题

I am having a hard time using $_FILES

I want to check if file upload field is empty or not then apply a condition such that if file upload is empty then the script doesn't try uploading the file. How do I enforce this?

回答1:

if($_FILES["file"]["error"] != 0) {
//stands for any kind of errors happen during the uploading
}

also there is

if($_FILES["file"]["error"] == 4) {
//means there is no file uploaded
}

回答2:

This should work

if ( ! empty($_FILES)) {...}

回答3:

The other answers didn't work for me. So I post my solution:

if($_FILES['theFile']['name']=='')
{
    //No file selected
}

回答4:

Here's what worked for me:

if ($_FILES['theFile']['tmp_name']!='') {
    // do this, upload file
} // if no file selected to upload, file isn't uploaded.

回答5:

You can use the UPLOAD_ERR_NO_FILE value:

function isset_file($file) {
    return (isset($file) && $file['error'] != UPLOAD_ERR_NO_FILE);
}

if(isset_file($_FILES['input_name'])) {
    // It's not empty
}

Updated: Since sending $_FILES['input_name'] may throw a Notice

function isset_file($name) {
    return (isset($_FILES[$name]) && $_FILES[$name]['error'] != UPLOAD_ERR_NO_FILE);
}

if(isset_file('input_name')) {
    // It's not empty
}

回答6:

this question is duplicate but your answer is is_uploade_file() function.

回答7:

if(!empty($_FILES['myFileField'])) {
    // file field is not empty..
} else {
    // no file uploaded..
}

来源：https://stackoverflow.com/questions/10096977/how-to-check-if-the-file-input-field-is-empty

标签

php

validation

file-upload

input-field