Pangram checker

You are encouraged to solve this task according to the task description, using any language you may know.
A pangram is a sentence that contains all the letters of the English alphabet at least once.

For example:   The quick brown fox jumps over the lazy dog.



Task

Write a function or method to check a sentence to see if it is a   pangram   (or not)   and show its use.



Related tasks

   determine if a string has all the same characters
   determine if a string has all unique characters


sub isPangram$(t$, l1$)
	local lt, ll, r$, i, cc, ic
 
	if numparams = 1 then
		l1$ = "abcdefghijklmnopqrstuvwxyz"
	end if
 
	t$ = lower$(t$)
	ll = len(l1$)
	for i = 1 to ll
		r$ = r$ + " "
	next
	lt = len(t$)
	cc = asc("a")
 
	for i = 1 to lt
		ic = asc(mid$(t$, i, 1)) - cc + 1
		if ic > 0 and ic <= ll then
			mid$(r$, ic, 1) = chr$(ic + cc - 1)
		end if
	next i
 
	if l1$ = r$ then return "true" else return "false" end if
 
end sub
 
print isPangram$("The quick brown fox jumps over the lazy dog.")   // --> true
print isPangram$("The quick brown fox jumped over the lazy dog.")  // --> false
print isPangram$("ABC.D.E.FGHI*J/KL-M+NO*PQ R\nSTUVWXYZ")          // --> true