How can I validate file types in my application?

How can I validate file types in my application?

You can validate file types by checking the file extension and MIME type. What programming language are you using?

I'm using JavaScript. Can you provide an example?

Sure! You can use the following code snippet to validate file types in JavaScript:

function validateFileType(file) {
    const allowedTypes = ['image/jpeg', 'image/png', 'application/pdf'];
    return allowedTypes.includes(file.type);
}

This checks if the file's MIME type is in the allowed list.

What if I want to restrict the file size as well?

You can add a size check like this:

function validateFile(file) {
    const allowedTypes = ['image/jpeg', 'image/png', 'application/pdf'];
    const maxSize = 2 * 1024 * 1024; // 2MB
    return allowedTypes.includes(file.type) && file.size <= maxSize;
}

This will ensure the file is both the correct type and within the size limit.