C语言字符串函数大全

函数名:strrev功能:串倒转用法:char*strrev(char*str);程序例:#include#includeintmain(void){char*forward="string";printf("Beforestrrev():%s\n",forward);strrev(forward);printf("Afterstrrev():%s\n",forward);return0;}函数名:strncpy功能:串拷贝用法:char*strncpy(char*destin,char*source,intmaxlen);程序例:#include#includeintmain(void){charstring[10];char*str1="abcdefghi";strncpy(string,str1,3);string[3]='\0';printf("%s\n",string);return0;}函数名:strcat功能:字符串拼接函数用法:char*strcat(char*destin,char*source);程序例:#include#includeintmain(void){chardestination[25];char*blank="",*c="C++",*Borland="Borland";strcpy(destination,Borland);strcat(destination,blank);strcat(destination,c);printf("%s\n",destination);return0;}函数名:stpcpy功能:拷贝一个字符串到另一个用法:char*stpcpy(char*destin,char*source);程序例:#include#includeintmain(void){charstring[10];char*str1="abcdefghi";stpcpy(string,str1);printf("%s\n",string);return0;}函数名:strchr功能:在一个串中查找给定字符的第一个匹配之处\用法:char*strchr(char*str,charc);程序例:#include#includeintmain(void){charstring[15];char*ptr,c='r';strcpy(string,"Thisisastring");ptr=strchr(string,c);if(ptr)printf("Thecharacter%cisatposition:%d\n",c,ptr-string);elseprintf("Thecharacterwasnotfound\n");return0;}函数名:strcmp功能:串比较用法:intstrcmp(char*str1,char*str2);看Asic码，str1>str2，返回值>0；两串相等，返回0程序例:#include#includeintmain(void){char*buf1="aaa",*buf2="bbb",*buf3="ccc";intptr;ptr=strcmp(buf2,buf1);if(ptr>0)printf("buffer2isgreaterthanbuffer1\n");elseprintf("buffer2islessthanbuffer1\n");ptr=strcmp(buf2,buf3);if(ptr>0)printf("buffer2isgreaterthanbuffer3\n");elseprintf("buffer2islessthanbuffer3\n");return0;}函数名:strncmpi功能:将一个串中的一部分与另一个串比较,不管大小写用法:intstrncmpi(char*str1,char*str2,unsignedmaxlen);程序例:#include#includeintmain(void){char*buf1="BBB",*buf2="bbb";intptr;ptr=strcmpi(buf2,buf1);if(ptr>0)printf("buffer2isgreaterthanbuffer1\n");if(ptr#includeintmain(void){charstring[10];char*str1="abcdefghi";strcpy(string,str1);printf("%s\n",string);return0;}函数名:strcspn功能:在串中查找第一个给定字符集内容的段用法:intstrcspn(char*str1,char*str2);程序例:#include#include#includeintmain(void){char*string1="1234567890";char*string2="747DC8";intlength;length=strcspn(string1,string2);printf("Characterwherestringsintersectisatposition%d\n",length);return0;}函数名:strdup功能:将串拷贝到新建的位置处用法:char*strdup(char*str);程序例:#include#include#includeintmain(void){char*dup_str,*string="abcde";dup_str=strdup(string);printf("%s\n",dup_str);free(dup_str);return0;}函数名:stricmp功能:以大小写不敏感方式比较两个串用法:intstricmp(char*str1,char*str2);程序例:#include#includeintmain(void){char*buf1="BBB",*buf2="bbb";intptr;ptr=stricmp(buf2,buf1);if(ptr>0)printf("buffer2isgreaterthanbuffer1\n");if(ptr字符串的指针用法:char*strerror(interrnum);程序例:#include#includeintmain(void){char*buffer;buffer=strerror(errno);printf("Error:%s\n",buffer);return0;}函数名:strcmpi功能:将一个串与另一个比较,不管大小写用法:intstrcmpi(char*str1,char*str2);程序例:#include#includeintmain(void){char*buf1="BBB",*buf2="bbb";intptr;ptr=strcmpi(buf2,buf1);if(ptr>0)printf("buffer2isgreaterthanbuffer1\n");if(ptr#includeintmain(void){char*buf1="aaabbb",*buf2="bbbccc",*buf3="ccc";intptr;ptr=strncmp(buf2,buf1,3);if(ptr>0)printf("buffer2isgreaterthanbuffer1\n");elseprintf("buffer2islessthanbuffer1\n");ptr=strncmp(buf2,buf3,3);if(ptr>0)printf("buffer2isgreaterthanbuffer3\n");elseprintf("buffer2islessthanbuffer3\n");return(0);}函数名:strncmpi功能:把串中的一部分与另一串中的一部分比较,不管大小写用法:intstrncmpi(char*str1,char*str2);程序例:#include#includeintmain(void){char*buf1="BBBccc",*buf2="bbbccc";intptr;ptr=strncmpi(buf2,buf1,3);if(ptr>0)printf("buffer2isgreaterthanbuffer1\n");if(ptr#includeintmain(void){char*buf1="BBBccc",*buf2="bbbccc";intptr;ptr=strnicmp(buf2,buf1,3);if(ptr>0)printf("buffer2isgreaterthanbuffer1\n");if(ptr#includeintmain(void){char*string="abcdefghijklmnopqrstuvwxyz";charletter='x';printf("stringbeforestrnset:%s\n",string);strnset(string,letter,13);printf("stringafterstrnset:%s\n",string);return0;}函数名:strpbrk功能:在串中查找给定字符集中的字符用法:char*strpbrk(char*str1,char*str2);程序例:#include#includeintmain(void){char*string1="abcdefghijklmnopqrstuvwxyz";char*string2="onm";char*ptr;ptr=strpbrk(string1,string2);if(ptr)printf("strpbrkfoundfirstcharacter:%c\n",*ptr);elseprintf("strpbrkdidn'tfindcharacterinset\n");return0;}函数名:strrchr功能:在串中查找指定字符的最后一个出现用法:char*strrchr(char*str,charc);程序例:#include#includeintmain(void){charstring[15];char*ptr,c='r';strcpy(string,"Thisisastring");ptr=strrchr(string,c);if(ptr)printf("Thecharacter%cisatposition:%d\n",c,ptr-string);elseprintf("Thecharacterwasnotfound\n");return0;}函数名:strset功能:将一个串中的所有字符都设为指定字符用法:char*strset(char*str,charc);程序例:#include#includeintmain(void){charstring[10]="123456789";charsymbol='c';printf("Beforestrset():%s\n",string);strset(string,symbol);printf("Afterstrset():%s\n",string);return0;}函数名:strspn功能:在串中查找指定字符集的子集的第一次出现用法:intstrspn(char*str1,char*str2);程序例:#include#include#includeintmain(void){char*string1="1234567890";char*string2="123DC8";intlength;length=strspn(string1,string2);printf("Characterwherestringsdifferisatposition%d\n",length);return0;}函数名:strstr功能:在串中查找指定字符串的第一次出现用法:char*strstr(char*str1,char*str2);程序例:#include#includeintmain(void){char*str1="BorlandInternational",*str2="nation",*ptr;ptr=strstr(str1,str2);printf("Thesubstringis:%s\n",ptr);return0;}函数名:strtod功能:将字符串转换为double型值用法:doublestrtod(char*str,char**endptr);程序例:#include#includeintmain(void){charinput[80],*endptr;doublevalue;printf("Enterafloatingpointnumber:");gets(input);value=strtod(input,&endptr);printf("Thestringis%sthenumberis%lf\n",input,value);return0;}函数名:strtok功能:查找由在第二个串中指定的分界符分隔开的单词用法:char*strtok(char*str1,char*str2);程序例:#include#includeintmain(void){charinput[16]="abc,d";char*p;/*strtokplacesaNULLterminatorinfrontofthetoken,iffound*/p=strtok(input,",");if(p)printf("%s\n",p);/*AsecondcalltostrtokusingaNULLasthefirstparameterreturnsapointertothecharacterfollowingthetoken*/p=strtok(NULL,",");if(p)printf("%s\n",p);return0;}函数名:strtol功能:将串转换为长整数用法:longstrtol(char*str,char**endptr,intbase);程序例:#include#includeintmain(void){char*string="87654321",*endptr;longlnumber;/*strtolconvertsstringtolonginteger*/lnumber=strtol(string,&endptr,10);printf("string=%slong=%ld\n",string,lnumber);return0;}函数名:strupr功能:将串中的小写字母转换为大写字母用法:char*strupr(char*str);程序例:#include#includeintmain(void){char*string="abcdefghijklmnopqrstuvwxyz",*ptr;/*convertsstringtouppercasecharacters*/ptr=strupr(string);printf("%s\n",ptr);return0;}函数名:swab功能:交换字节用法:voidswab(char*from,char*to,intnbytes);程序例:#include#include#includecharsource[15]="rFnakoBlrnad";chartarget[15];intmain(void){swab(source,target,strlen(source));printf("Thisistarget:%s\n",target);return0;}