Sometimes, we want to check file MIME type with JavaScript before upload.
In this article, we’ll look at how to check file MIME type with JavaScript before upload.
How to check file MIME type with JavaScript before upload?
To check file MIME type with JavaScript before upload, we get the type property of the file object.
For instance, we write
const [fileVariable] = document.getElementsById("fileId").files;
if (fileVariable.type.match("image.*")) {
alert("its an image");
}
to get the file input with getElementsById.
We get the selected files from the files property.
And then we get the MIME type of the file with fileVariable.type, which is a string.
Conclusion
To check file MIME type with JavaScript before upload, we get the type property of the file object.
