<pre name="code" class="cpp">/*
	strlen函式解析
*/
# include<stdio.h>
# include<malloc.h>
# include<string.h>

int main(void)
{
	char * c1 = "AbSjhhss";
	int len1 = strlen(c1);
	printf("len1 = %d\n", len1);     //len1 = 8

	char c2[] = {'a', '4', 'r', 't', 'd'};
	int len2 = strlen(c2);
	printf("len2 = %d\n", len2);    //..error..len2 = 9

	char c3[] = {'a', '4', 'r', 't', 'd', '\0'};
	int len3 = strlen(c3);
	printf("len3 = %d\n", len3);   //len3 = 5

	char c4[10] = "AbS";
	int len4 = strlen(c4);
	printf("len4 = %d\n", len4);   //len4 = 3 

	char c5[4];
	int len5 = strlen(c5);
	printf("len5 = %d\n", len5);  //len5 = 5
/*
	c5[0] = '\0';
	len5 = strlen(c5);
	printf("len5 = %d\n", len5);  //len5 = 0
*/
	c5[4] = '\0';
	len5 = strlen(c5);
	printf("len5 = %d\n", len5);  //len5 = 4

	return 0;
}

/*
	總結：如果字元陣列，
	   1.用字串(雙引號"")初始化，用strlen函式可以求出該字串的長度
	   2.用字元陣列的形式({'',''})初始化，必須在最後面新增一個元素'\0'才可以。

	所以：strlen() 從字元陣列首地址開始，一直找下去，直到遇到'\0'才停止
*/