What is the procedure to see that the optional file is detected? - Zend

What is the procedure to see that the optional file is detected?

- There is a use of receive() method that returns true for the file element which is not required.

- The file can be neglected when using the method mentioned above, as soon as the file gets opened it detected.

- The method returns the false in case of any error or the file hasn’t been copied or uploaded directly.

- There are other methods used to provide the detection of the file using the elements in normal HTML file.

- The methods can detect the file and provide the tools to make the file being detected.