c# - Question Mark (?) after session variable reference - What does that mean -


i have had code snippet comes modify. in there found such syntax.

session("lightboxid")?.tostring()

i didn't understand question mark (?) there means. no googling helped me hint

it performs null-check on session("lightboxid") before attempting call .tostring() on it.

msdn: null-conditional operators (c# , visual basic)


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