标签：源代码 c语言 字符串
头文件：my_string.h #ifndef __MY_STRING__ #define __MY_STRING__ /*十六进制数值字符串转整数*/ int ch_to_hex(const char* val_in,int size); /*判断给定字符串是否是十六进制数*/ int is_hex(const char* val,int size); /*判断给定字符串是否是数字*/ /*R_V:1(数字) 0(非数字)*/ int is_num(const char* val); /*字符转整数数字(对于是否是纯数字不做判断)*/ int ch_to_num(const char* val); /*将英文字母小写->大写*/ void to_upper( char* buf, int size); /*将英文字母大写->小写*/ void to_lower( char* buf, int size); /*去掉字符串左边的空格*/ /*R_V:-1 转换失败 转换后的字节长度*/ int left_trim(char* buf,int size); /*去掉字符串右边的空格*/ /*R_V:-1 转换失败 转换后的字节长度*/ int right_trim(char* buf,int size); /*去掉字符串两边的空格*/ /*R_V:-1 转换失败 转换后的字节长度*/ int trim(char* buf, int size); /*将字符串内部连续多个空格缩减为1个空格*/ void reduce_space(char* buf, int size); int split(const char* buf_in,int size_in,char* buf[],int size , char separator); void split_free(char* buf[],int size); #endif
源代码：my_string.c
#include<string.h>
#include<malloc.h>
#include<memory.h>
/*判断给定字符串是否是十六进制数*/
int is_hex(const char* val,int size)
{
int status = 1;
char* buf_tmp = malloc(size+1);
memset(buf_tmp,0,size+1);
memcpy(buf_tmp,val,size);
to_upper(buf_tmp,size);
for(int index= 0 ; index < size; index++)
{
/*碰到x跳过去*/
if(index == 1 && buf_tmp[index]==0x58) continue;
if((buf_tmp[index]>0x39 && buf_tmp[index] <0x41) || (unsigned char)buf_tmp[index] <0x30 || (unsigned char)buf_tmp[index] > 0x46 )
{
status = 0;
break;
}
}
free(buf_tmp);
return status;
}
/*判断给定字符串是否是数字*/
/*R_V:1(数字) 0(非数字)*/
int is_num(const char* val)
{
int status = 1;
int index = 0;
while(val[index])
{
if(val[index]>0x39 || val[index] <0x30)
{
/*非数字*/
status = 0;
break;
}
index++;
}
return status;
}
/*十六进制数值字符串转整数*/
int ch_to_hex(const char* val_in,int size)
{
int result = 0;
int bit_pos = 0;
char* val = malloc(size+1);
memset(val,0,size+1);
memcpy(val,val_in,size);
to_upper(val,size);
for(int index = size-1;index>=0;index--)
{
/*碰到x跳出去*/
if(index == 1 && val[index]==0x58) break;
if(val[index]>= 0x30 && val[index] <=0x39)
{
result = ((val[index] - 0x30) << (bit_pos++ * 4)) | result;
}
else
{
result = ((val[index] - 0x41 + 10) << (bit_pos++ * 4)) | result;
}
}
free(val);
return result;
}
/*字符转整数数字(对于是否是纯数字不做判断)*/
int ch_to_num(const char* val)
{
int index = 0;
/*标示是否为负数*/
int i_negative = 0;
/*判断字符串中的数字是否有负号*/
if(val[index] == ‘-‘)
{
i_negative = 1;
index++;
}
int result = val[index++] - 0x30;
while(val[index])
{
/*能进循环，说明不止一位数*/
result = result * 10;
result += (val[index++] - 0x30);
}
if(i_negative == 1) result = 0 - result;
return result;
}
/*将英文字母小写->大写*/
void to_upper( char* buf, int size)
{
if(!buf || size <= 0 ) return;
for(int index = 0 ; index < size; index++)
{
if(buf[index] >= 0x61 && buf[index] <= 0x7A)
{
buf[index] = buf[index] - 0x20;
}
}
}
/*将英文字母大写->小写*/
void to_lower( char* buf, int size)
{
if(!buf || size <= 0 ) return;
for(int index = 0 ; index < size; index++)
{
if(buf[index] >= 0x41 && buf[index] <= 0x5A)
{
buf[index] = buf[index] + 0x20;
}
}
}
/*去掉字符串左边的空格*/
/*R_V:-1 转换失败 转换后的字节长度*/
int left_trim(char* buf,int size)
{
if(!buf || size <= 0 ) return -1;
char* buf_tmp = malloc(size + 1);
memset(buf_tmp,0,size + 1);
int index = 0;
for( index = 0 ; index < size; index++)
{
if(buf[index] != 0x20) break;
}
memcpy(buf_tmp,buf+index,size - index);
strcpy(buf,buf_tmp);
free(buf_tmp);
return size - index;
}
/*去掉字符串右边的空格*/
/*R_V:-1 转换失败 转换后的字节长度*/
int right_trim(char* buf,int size)
{
if(!buf || size <= 0 ) return -1;
char* buf_tmp = malloc(size + 1);
memset(buf_tmp,0,size + 1);
int index = 0;
for(index = size - 1;index >= 0 ; index--)
{
if(buf[index] != 0x20) break;
}
memcpy(buf_tmp,buf,index+1);
strcpy(buf,buf_tmp);
free(buf_tmp);
return index+1;
}
/*去掉字符串两边的空格*/
/*R_V:-1 转换失败 转换后的字节长度*/
int trim(char* buf, int size)
{
int result = 0;
if((result= left_trim(buf,size)) == -1) return -1;
if((result= right_trim(buf,result)) == -1) return -1;
return result;
}
/*将字符串内部连续多个空格缩减为1个空格*/
void reduce_space(char* buf, int size)
{
int index = 0;
int index_tmp = 0;
int flag = 0 ;
char* buf_tmp = malloc(size+1);
memset(buf_tmp,0,size+1);
for(index =0;index<size;index++)
{
if(buf[index] != 0x20)
{
if(flag == 1)
{
buf_tmp[index_tmp++] = 0x20;
flag = 0;
}
buf_tmp[index_tmp++] = buf[index];
}
else
{
flag = 1;
}
}
memset(buf,0,size);
memcpy(buf,buf_tmp,index_tmp);
free(buf_tmp);
return;
}
int split(const char* buf_in,int size_in,char* buf[],int size , char separator)
{
int index = 0 ;
int count = 0 ;
int flag = 0;
for(index = 0;index < size_in; index++)
{
if(buf_in[index] == separator)
{
if(count == size) return count;
buf[count] = malloc(index - flag + 1);
memset(buf[count],0,index-flag+1);
memcpy(buf[count++],&buf_in[flag],index-flag);
flag = index + 1;
}
}
buf[count] = malloc(index - flag + 1);
memset(buf[count],0,index-flag+1);
memcpy(buf[count++],&buf_in[flag],index-flag);
return count;
}
void split_free(char* buf[],int size)
{
for(int index = 0; index < size; index++)
{
free(buf[index]);
}
}
标签：源代码 c语言 字符串
原文地址：http://wasteland.blog.51cto.com/926380/1614523
