c語言判斷是否是utf8字串，計算字元個數
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
/****************************************************************************
Unicode符號範圍 | UTF-8編碼方式
(十六進位制) | （二進位制)
0000 0000-0000 007F:0xxxxxxx
0000 0080-0000 07FF:110xxxxx 10xxxxxx
0000 0800-0000 FFFF:1110xxxx 10xxxxxx 10xxxxxx
0001 0000-001F FFFF:11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
0020 0000-03FF FFFF:111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
0400 0000-7FFF FFFF:1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
**************************************************************************/
unsigned char utf8_look_for_table[] =
{
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 1, 1};
#define UTFLEN(x) utf8_look_for_table[(x)]
//根據首位元組,獲取utf8字元所佔位元組數
inline int GetUtf8charByteNum(unsigned char ch)
{
int byteNum = 0;
if (ch >= 0xFC && ch < 0xFE)
byteNum = 6;
else if (ch >= 0xF8)
byteNum = 5;
else if (ch >= 0xF0)
byteNum = 4;
else if (ch >= 0xE0)
byteNum = 3;
else if (ch >= 0xC0)
byteNum = 2;
else if (0 == (ch & 0x80))
byteNum = 1;
return byteNum;
}
//判斷字串是否是utf8格式
int IsUtf8Format(const char *str)
{
int byteNum = 0;
unsigned char ch;
const char *ptr = str;
if (NULL == str)
return 0;
while (*ptr != '\0')
{
ch = (unsigned char)*ptr;
if (byteNum == 0) //根據首位元組特性判斷該字元的位元組數
{
if (0 == (byteNum = GetUtf8charByteNum(ch)))
return 0;
}
else //多位元組字元,非首位元組格式:10xxxxxx
{
if ((ch & 0xC0) != 0x80)
return 0;
}
byteNum--;
ptr++;
}
if (byteNum > 0)
return 0;
return 1;
}
//計算utf8字串字元個數
int GetUtf8Length(char *str)
{
int clen = 0;
int len = 0;
int byteNum = 0;
unsigned char ch;
char *ptr = str;
if (NULL == str)
return 0;
clen = strlen(str);
while (*ptr != '\0' && len < clen)
{
ch = (unsigned char)*ptr;
if (0 == (byteNum = GetUtf8charByteNum(ch)))
return 0;
ptr += byteNum;
len++;
}
return len;
}
int GetChargeNum(int len)
{
int num = 0;
if (len > 70 && len <= 500)
{
if (!len % 67)
num = len / 67;
else
num = len / 67 + 1;
}
else if (len > 0)
num = 1;
return num;
}
int main(int argc, char **argv)
{
//char *str = "hello 你好呀！";
char *str;
int len = 0;
int num = 0;
if (argc < 2)
return 0;
str = argv[1];
printf("%s\n", str);
if (!IsUtf8Format(str))
{
printf("the text is not the Format of utf8\n");
return 0;
}
if (!(len = GetUtf8Length(str)))
return 0;
printf("the length of text: %d\n", len);
if (!(num = GetChargeNum(len)))
return 0;
printf("the chargeNumber of sms: %d\n", num);
return 1;
}