VB返回值的问题

bmin = Tan(φklw * 3.14 / 180) * (-X2(1)) + Y2(1)
bmax = Tan(φklw * 3.14 / 180) * (-X1(i)) + Y1(i)
beq = (bmin + bmax) / 2
Vknew1 = Vknew1(b)             '调用了子函数Vknew(b)的值

While (Vknew1 < V(i))
bmin = beq
beq = (bmin + bmax) / 2
Vknew1 = Vknew1(b)
Wend

While (Vknew1 > V(i))
bmax = beq
beq = (bmin + bmax) / 2
Vknew1 = Vknew1(b)
Wend      

怎么才能将没一个While……wend循环的最终值返还到它们的上面，即返回给Vknew1，然后进行条件判断，是否要重新循环。
忘指教