C语言实例：函数指针

函数指针：函数指针数组的使用：

不带参数和返回值的函数指针：

#include <stdio.h>
#include <stdlib.h>

//定义一个没有返回值也没有入口参数的函数指针
typedef void (CONTROL_FLOW_FUNCTION)();

void Function1()
{
    printf("  This is printed by function1 !!!\n");
}
void Function2()
{
    printf("  22222222\n");
    printf("    22222222\n");
}
void Function3()
{
    printf("  This is printed by function3......\n");
}

CONTROL_FLOW_FUNCTION *ControlFlowFunctions[] = {
    Function1,
    Function2,
    Function3,
    NULL
};

char *ControlFlowFunctionNames[] = {
    "Function1",
    "Function2",
    "Function3",
    NULL
};

int main()
{
    ;
    printf("main start!\n");
    ; ControlFlowFunctions[i]!=NULL; i++){
        printf("ControlFlow.%s\n", ControlFlowFunctionNames[i]);
        ControlFlowFunctions[i]();
    }
    printf("main end!\n");
}

带参数和返回值的函数指针：

#include <stdio.h>
#include <stdlib.h>

//定义一个函数指针类型
typedef int (CONTROL_FILTER_FUNCTION)(int dat);

int Function1(int data)
{
    printf("Check if data can be exactly divisible by 2.\n");
     == )
        ;
    else
        ;
}
int Function2(int data)
{
    printf("Check if data can be exactly divisible by 3.\n");
     == )
        ;
    else
        ;
}
int Function3(int data)
{
    printf("Check if data can be exactly divisible by 5.\n");
     == )
        ;
    else
        ;
}

CONTROL_FILTER_FUNCTION *ControlFilterFunctions[] = {
    Function1,
    Function2,
    Function3,
    NULL
};

char *ControlFilterFunctionNames[] = {
    "Function1",
    "Function2",
    "Function3",
    NULL
};

int main()
{
    ;
    ;
    printf("==Check if data can be exactly divisible by 2 or 3 or 5==.\n");
    ; ControlFilterFunctions[i]!=NULL; i++){
        printf("ControlFilter.%s\n", ControlFilterFunctionNames[i]);
        if(ControlFilterFunctions[i](data))
        {
            printf("YES::%d can be exactly divisible by 2 or 3 or 5.\n", data);
            ;
        }
    }
    printf("NO::%d can't be exactly divisible by 2 or 3 or 5.\n", data);
    ;
}