typedef的使用3

#include <stdio.h>
#include <string.h>//不加还能跑，加上反而跑不了了。。。笑哭
#pragma warning(disable:4996)//要这句跟上面那个包含放在一起。否则会有一个警告组织编译。


//字符串拷贝函数：
const char * myStrcat(const char *,const char *);

typedef const char * MYSTRCAT1(const char *,const char *);
//这里是定义了一个MYSTRCAT1这种类型的对象，本身是一个函数

typedef const char * (*MYSTRCAT2)(const char *, const char *);
//定义了一个指向这种函数的地址

//回调函数：

const char * myback(const char * (const char *, const char *), const char *, const char *);

const char * myback1(MYSTRCAT1, const char *, const char *);

const char * myback2(MYSTRCAT2, const char *, const char *);



int main(){
    //char *p = myStrcat("hello", " world");
    //printf(p);
    //free(p);

    /*
    char *pf = myStrcat;
    char *p1 = myback(pf, "hello", " world");
    printf(p1);
    free(p1);
    */
/*
    MYSTRCAT1 *function = &myStrcat;
    char *p2 = myback1(function, "hello", " world");
    printf(p2);
    free(p2);
*/

/*
    MYSTRCAT2 function2 = myStrcat;
    char *p3 = myback2(function2, "hello", " world");
    printf(p3);
    free(p3);
*/

/*
    MYSTRCAT1 * function1[10];
    function1[0] = &myStrcat;
    char *p4 = myback1(function1[0], "hello", " world");
    printf(p4);
    free(p4);
*/
    MYSTRCAT2 function2[3];
    function2[2] = myStrcat;
    char *p5 = myback2(function2[2], "hello", " world");
    printf(p5);
    free(p5);




    getchar();
    return 0;




}

const char * myStrcat(const char *str1, const char * str2){
    if (str1 != NULL&&str2 != NULL){
        char *p = malloc(strlen(str1) + strlen(str2) + 1);
        strcpy(p, str1);
        strcat(p, str2);
        return p;
    }
}

const char * myback(const char * func(const char *, const char *), const char * str1, const char * str2){
    return func(str1, str2);
}
const char * myback1(MYSTRCAT1 func, const char *str1, const char *str2){
    return func(str1, str2);
}
const char * myback2(MYSTRCAT2 func, const char *str1, const char *str2){
    return func(str1, str2);
}