  We study the level-one irreducible highest weight representations of the
quantum affine superalgebra $U_q[\hat{sl(N|1)}]$, and calculate their
characters and supercharacters. We obtain bosonized q-vertex operators acting
on the irreducible $U_q[\hat{sl(N|1)}]$-modules and derive the exchange
relations satisfied by the vertex operators. We give the bosonization of the
multi-component super $t-J$ model by using the bosonized vertex operators.
