I am sorry that i don't state my problem clearly.
Your method is a good way to solve the problem,Jiri.
But I want to ask you for another.
In fact, the array is definitioned 
the array is definitioned in text section,
So I can't change the value of the definitioned vector table.
Now I want to set a new arrary to store the ISRs' address,like this:
uint32_t IntcIsrVectorTable[750] = {(uint32_t)(&dummy),(uint32_t)(&dummy) ...};
and then
INTC.IACKR[0].R = (uint32_t)&IntcIsrVectorTable;
last I replace the corresponding value of the array with ISR address,like:
void Pit0Ch0Isr(void)
{
PIT_0.TIMER[0].TFLG.B.TIF = 1; //clear the flag
SIUL2.GPDO[30].B.PDO_4n3 = ~SIUL2.GPDO[30].B.PDO_4n3; //turn
}
IntcIsrVectorTable[226] = (uint32_t)(&Pit0Ch0Isr);
and then I enable the interrupt,I find that I can't enter the changed ISR,what happen?
Thank for your help!