C语言的typedef用法

案例1： 

#include <stdio.h>
#include <string.h>
#include <malloc.h>


typedef int zhangsan; //为int在多取一个名字   zhangsan等价于int

struct Student{
	int sid;
	char sname[100];
	char sex;
	
} ST;

int main() {

	int i = 10;  //等价于zhangsan i=10
	zhangsan j = 20;
	printf("%d", j);


	char c = '\0';
	printf("%c\n", c);
	printf("c输出得：%d\n", (int)c);

	struct Student st;
	struct Student * ps = &st;

	
	ST.sid=12;
	ST.sex = 'n';
	strcpy_s(ST.sname , "lisi");
	printf("%c\n", ST.sex);
	printf("%d\n", ST.sid);
	printf("%s\n", ST.sname);

	while (true){}
	return 0;
}

案例2：

#include <stdio.h>
#include <string.h>
#include <malloc.h>


typedef int zhangsan; //为int在多取一个名字   zhangsan等价于int

 typedef struct Student{
	int sid;
	char sname[100];
	char sex;

} ST;

int main() {

	int i = 10;  //等价于zhangsan i=10
	zhangsan j = 20;
	printf("%d", j);


	char a = '\0';
	printf("%c\n", a);

	struct Student st;
	struct Student * ps = &st;

	ST st2;         //等价于  struct Student st;
	st2.sid = 12;
	st2.sex = 'n';
	strcpy_s(st2.sname, "lisi");
	printf("%c\n", st2.sex);
	printf("%d\n", st2.sid);
	printf("%s\n", st2.sname);

	while (true) {}
	return 0;
}

 案例3：

#include <stdio.h>
#include <string.h>
#include <malloc.h>

typedef int zhangsan; //为int在多取一个名字   zhangsan等价于int

 typedef struct Student{
	int sid;
	char sname[100];
	char sex;

} * PST;   //等价于struct Student * 

int main(void) {

	struct Student st;
	PST ps = &st;
	ps->sid = 99;
	printf("%d\n", ps->sid);
	
	while (true) {}
	return 0;
}

案例4：

#include <stdio.h>
#include <string.h>
#include <malloc.h>



typedef int zhangsan; //为int在多取一个名字   zhangsan等价于int

typedef struct Student
{
	int sid;
	char sname[100];
	char sex;

} *PSTU,STU;   //PSTU等价于struct Student * （PSTU表示结构体指针）,STU等价于struct Student st （结构体本身）

int main(void) {

	STU st;
	PSTU ps = &st;
	ps->sid = 99;
	printf("%d\n", ps->sid);

	while (true) {}
	return 0;
}