javascript - jquery / asp.net - get the number of images in a folder where the first two characters of the file name are XX -

I am looking for the best way to get the total number of images in a folder where the first two letters on the file name are XX And place this number in a variable.

For example - I have a picture in which the following images are:

XX-01.jpg
XX-02.jpg
XX-03.jpg
YY-01.jpg
ZZ-01.jpg

So I will populate the variable with 3 in this case.

Do anyone know any way to do this?

Do not do it in jQuery.

Instead of go to server side. These are like bad codes, other developers will curse you.