HTML input file selection event not firing upon selecting the same file

HTML input file selection event not firing upon selecting the same file

Is there any chance to detect every file selection the user made for an HTML input of type file element?
This was asked many times before, but the usually proposed onchange event doesn’t fire if the user select the same file again.

Solutions/Answers:

Solution 1:

Set the value of the input to null on each onclick event. This will reset the input‘s value and trigger the onchange event even if the same path is selected.

input.onclick = function () {
    this.value = null;
};

input.onchange = function () {
    alert(this.value);
};​

Here’s a DEMO.

Note: It’s normal if your file is prefixed with ‘C:\fakepath\’. That’s a security feature preventing JavaScript from knowing the file’s absolute path. The browser still knows it internally.

Solution 2:

<form enctype='multipart/form-data'>
    <input onchange="alert(this.value); this.value=null; return false;" type='file'>
    <br>
    <input type='submit' value='Upload'>
</form>

this.value=null; is only necessary for Chrome, Firefox will work fine just with return false;

Here is a FIDDLE

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Solution 3:

In this article, under the title “Using form input for selecting”

http://www.html5rocks.com/en/tutorials/file/dndfiles/

<input type="file" id="files" name="files[]" multiple />

<script>
function handleFileSelect(evt) {

    var files = evt.target.files; // FileList object

    // files is a FileList of File objects. List some properties.
    var output = [];
    for (var i = 0, f; f = files[i]; i++) {
     // Code to execute for every file selected
    }
    // Code to execute after that

}

document.getElementById('files').addEventListener('change', 
                                                  handleFileSelect, 
                                                  false);
</script>

It adds an event listener to ‘change’, but I tested it and it triggers even if you choose the same file and not if you cancel.

Solution 4:

Use onClick event to clear value of target input, each time user clicks on field. This ensures that the onChange event will be triggered for the same file as well. Worked for me 🙂

onInputClick = (event) => {
    event.target.value = ''
}

<input type="file" onChange={onFileChanged} onClick={onInputClick} />

Using TypeScript

onInputClick = ( event: React.MouseEvent<HTMLInputElement, MouseEvent>) => {
    const element = event.target as HTMLInputElement
    element.value = ''
}

Solution 5:

Do whatever you want to do after the file loads successfully.just after the completion of your file processing set the value of file control to blank string.so the .change() will always be called even the file name changes or not. like for example you can do this thing and worked for me like charm

   $('#myFile').change(function () {
       LoadFile("myFile");//function to do processing of file.
       $('#myFile').val('');// set the value to empty of myfile control.
    });