全局变量和局部变量

csbz580

1.全局变量（也叫外部变量）分为外部全局变量（extern修饰）和静态全局变量（static修饰）
2.静态全局变量（static修饰）------只能在被定义在的源程序使用，而外部全局变量（extern修饰）既可在被定义在的源程序使用，也可以在别的源程序的函数引用
3.在函数前定义过全局变量，那在这个函数里面使用时，可以不说明，通常要在函数前做全局变量做说明
例如：
#include<stdio.h>

int a = 0;
void print()
{
   
    printf("global variable a=%d\n",a);
}
int main()
{
   
    print();

    return 0;
}
全局变量a在print（）函数前有定义，所以在print（）函数中使用无需说明，但下面的代码将会运行出错。

#include<stdio.h>

void print()
{
   
    printf("global variable a=%d\n",a);
}
int a = 0;//全局变量没有在print（）前声明
int main()
{
   
    print();

    return 0;
}
可以在print（）函数里面的printf（）语句前加一个 extern int a;


4.局部变量是相对于全局变量来说的，局部变量就是定义在函数体里面的变量。当然，由于形参相当于函数中定义的变量，所以形参也属于一种局部变量。













https://m.vk.com/public212725457
https://m.vk.com/public212730424
https://m.vk.com/public212730574
https://m.vk.com/public212730616
https://m.vk.com/public212745225
https://m.vk.com/public212746092
https://m.vk.com/public212754170
https://m.vk.com/public212754213
https://m.vk.com/public212754471
https://m.vk.com/public212754531
https://m.vk.com/public212769260
https://m.vk.com/public212769540
https://m.vk.com/public212789644
https://m.vk.com/public212789982
https://m.vk.com/public212790084
https://m.vk.com/public212790258
https://m.vk.com/public212811877
https://m.vk.com/public212812193
https://m.vk.com/public212834815
https://m.vk.com/public212834919
https://m.vk.com/public212835081
https://m.vk.com/public212835522
https://m.vk.com/public212862497
https://m.vk.com/public212862572
https://m.vk.com/public212862608
https://m.vk.com/public212878952
https://m.vk.com/public212890225
https://m.vk.com/public212890303
https://m.vk.com/public212910654
https://m.vk.com/public212910847
https://m.vk.com/product-212910847_6842462
https://m.vk.com/uslugi-21291084 ... 847_6842462%2Fquery
https://m.vk.com/public212931875
https://m.vk.com/public212931996
https://m.vk.com/public212932447
https://m.vk.com/public212932731
https://m.vk.com/public212725187
https://m.vk.com/public212730510
https://dribbble.com/xabzs
https://dribbble.com/shots/18334578-bz
https://dribbble.com/dgbjzs
https://dribbble.com/shots/18334830-1
https://dribbble.com/njbzs
https://dribbble.com/shots/18352001-1
https://dribbble.com/ncbzgs
https://dribbble.com/shots/18352286-bz
https://dribbble.com/szbzfw
https://dribbble.com/shots/18518953-bz
https://dribbble.com/kmbjzs
https://dribbble.com/shots/18519005-1
https://dribbble.com/whbzs
https://dribbble.com/shots/18567245-1
https://dribbble.com/zzbzs
https://dribbble.com/shots/18567397-bz
https://dribbble.com/csbjz
https://dribbble.com/shots/18582636-1
https://dribbble.com/jnbjz
https://dribbble.com/shots/18582783-1
https://dribbble.com/fzbzfw
https://dribbble.com/shots/18584849-bz
https://dribbble.com/shzhbjz
https://dribbble.com/shots/18585318-1
https://dribbble.com/gzbzgs
https://dribbble.com/shots/18591493-1
https://dribbble.com/sjzbjz
https://dribbble.com/shots/18591645-bz
https://dribbble.com/hdbjz
https://dribbble.com/shots/18602951-1
https://dribbble.com/cdbzs
https://dribbble.com/cqbzs
https://dribbble.com/shots/18669060-1
https://dribbble.com/hzbzs
https://dribbble.com/shots/18669240-bz
https://dribbble.com/shbjzfw
https://dribbble.com/shots/18692319-1
https://dribbble.com/tjbjz
https://dribbble.com/shots/18693341-bz