C测试小程序

C测试小程序

1、 字符串类

1.1 strstr

功能：查找和获取子串

void test_strstr()

{

char *str="Borland International";

char *str1="B",*ptr1;

char *str2="na",*ptr2;

char *str3="",*ptr3;

ptr1=strstr(str,str1);

printf("The substring1 is: %s/n", ptr1);//Borland International

ptr2=strstr(str,str2);

printf("The substring2 is: %s/n", ptr2);//national

ptr3=strstr(str,str3);

printf("The substring3 is: %s/n", ptr3); //Borland International

}

/*****************************************************

char *strstr( const char *string, const char *strCharSet );

Each of these functions returns a pointer to the first occurrence of strCharSet in string,

or NULL if strCharSet does not appear in string. If strCharSet points to a string of zero length,

the function returns string.

******************************************************/

1.2 atoi和_itoa

功能：char和int之间的互相转换

void char2int_1()

{

char* temp1="123";

int a1=atoi(temp1);

printf("char2int_1()/ta1+1=%d/n",a1+1);//124

}

void int2char_1()

{

char temp[20];

char* retp;

int a2=65;

retp=_itoa(a2,temp,16);

printf("int2char_1/tretp=%s/n",retp);//41

printf("int2char_1/ttemp=%s/n",temp);//41

retp=_itoa(a2,temp,10);

printf("int2char_1/tretp=%s/n",retp);//65

printf("int2char_1/ttemp=%s/n",temp);//65

}

void int2char_2()

{

char temp[20];

int a2=65;

sprintf(temp,"%d",65);

printf("int2char_2/ttemp=%s/n",temp);//65

}

1.3 nospace

功能：去除字符串两边的空格

char* noleftspace(char* str)

{

char* temp;

printf("before noleftspace=%s/n",str);

while(*str!='/0')

{

if(*str==' ')

{

str=str+1;

temp=str;

}

else

{

temp=str;

break;

}

}

printf("after noleftspace=%s/n",temp);

return temp;

}

char* norightspace(char* str)

{

int length=strlen(str);

int a=length-1;

char* temp;

*str='1';

printf("before noleftspace=%s/n",str);

while(a>0)

{

if(*(str+a)!=' ')

{

(char*)str;

*(str+a+1)='/0';

break;

}

else

a--;

}

printf("after noleftspace=%s/n",str);

return str;

}

1.4 strchr

功能：查找字符串中某个字符出现的第一个位置

int test_strchr(void) //查找字符串中第一个匹配的字符的位置

{

char string[15];

char *ptr, c = 'r';

strcpy(string, "This is a string");

ptr = strchr(string, c);

if (ptr)

printf("The character %c is at position: %d/n", c, ptr-string); //12

else

printf("The character was not found/n");

printf("ptr=%s/n",ptr);//ring

return 0;

}

1.5 strcspn

功能：在string中，第一次出现strCharSet中任意一个字符的位置

/*******************************************************

size_t strcspn( const char *string, const char *strCharSet );

在string中，第一次出现strCharSet中任意一个字符的位置

*********************************************************/

int test_strcspn(void)

{

char *string = "D23557890"; //string1中的D出现在string的第0个位置

char *string1 = "7DC8";

int length1;

char *string2 = "45"; //string2中的5出现在string的第3个位置

int length2;

length1 = strcspn(string, string1);

printf("Character where strings intersect is at position %d/n", length1); //5

length2 = strcspn(string, string2);

printf("Character where strings intersect is at position %d/n", length2); //3

return 0;

}

1．6 strpbrk

功能：查找在string中出现的来自strCharSet第一个字符，并返回指向它的指针

/**************************************************************

char *strpbrk( const char *string, const char *strCharSet );

查找在string中出现的来自strCharSet第一个字符，并返回指向它的指针

Each of these functions returns a pointer to the first occurrence of any character

from strCharSet in string, or a NULL pointer if the two string arguments have no characters in common.

****************************************************************/

int test_strpbrk(void) //查找string2中字符在string1中出现的位置

{

char *string1 = "abcdefghi3jklmnopqrstuvwxyz";

char *string2 = "9876543210";

char *ptr;

ptr = strpbrk(string1, string2);

if (ptr)

{

printf("strpbrk found first character: %c/n", *ptr); //3

printf("the position of ptr is %d",(ptr-string1)); //9

}

else

printf("strpbrk didn't find character in set/n");

return 0;

}

1.7 strspn

功能：string中第一个不在strCharSet中的字符的位置

/***********************************************************

size_t strspn( const char *string, const char *strCharSet );

string中第一个不在strCharSet中的字符的位置

***********************************************************/

int test_strspn(void)

{

char *string1 = "1234567890"; //5不在string2中

char *string2 = "000000213985fDC84";

int length;

length = strspn(string1, string2);

printf("Character where strings differ is at position %d/n", length); //5

return 0;

}

1.8 strtok

功能：拆分字符串

char string[] = "10.8.'2.173--xense rver3";

char seps[] = "'- '";

char *token;

void main( void )

{

printf( "%s/n/nTokens:/n", string );

token = strtok( string, seps );

while( token != NULL )

{

printf( " %s/n", token );

token = strtok( NULL, seps );

}

}

/***********************************************

10.8.

2.173

xense

rver3

************************************************/

1.9 access

功能：判断一个文件是否存在

printf ("%d",access("111.txt",0));//存在