讨论带限函数的Shannon采样定理截断误差的点态、一致和积分3种估计．对于点态
情形，用Dirichilet核的计算方法算出截断误差的阶为O(1/N)；对于一致情形和积分情形，当
函数满足一定的衰减条件时，可分别得到收敛阶的一致及积分估计．

In this paper we discuss the truncated error estimate on Shannon sampling theorem of bandlimited functions. We mainly focus on error of pointwise type, uniform type and integral type. In pointwise type, we use the method of calcuating Dirichlet kernel and obtain the order O(1/N); in uniform and integral type, by calculating the decaying condition imposed on the function, we can get the uniform and integral estimate.