如何检查字符串是否由C中的数字或字母组成 [英] How to check if string consist of numeric or alphabet in C

问题描述

我需要一些识别字符串的帮助。我有这样的传入字符串

 * H1999999＃

它可能与

 * H1000000＃〜* H1999999＃

不同有时它是

 * H1FINE＃或* H1MED＃

或介于两者之间的任何其他文本。现在我已经完成了解析数字字符串并复制了整数值到一个缓冲区。这是代码。

 char H1subbuff [10]; 
 char head1 [4]; 
 char Initial [2]; 
 
 char * ptr; 
 
 memcpy（Initial，& rec [0]，1）; 
 Initial [1] ='\0'; 
 
 memcpy（head1，& rec [0]，3）; 
 head1 [3] ='\0'; 
 
 
 
 if（（strcmp（head1，* H1）== 0）&&（rec [9] =='＃'））
 {
 memcpy（H1subbuff，& rec [3]，6）; 
 H1subbuff [6] ='\0'; 
 
 H1Val = strtol（H1subbuff，& ptr，10）; 
 
 //显示H1VAL 
} 
 

现在我的查询是怎么回事检查字符串是否由数字或字母组成。我需要检查* H1和＃之间的部分是数字还是字母，如果它是数字，我可以使用

 strtol（）

将int值复制到缓冲区中。如何将字母或文本复制到缓冲区？



注意： - 上面两个字符串的字符串长度不一样。



我尝试了什么：



我试图将数值复制到缓冲区。

解决方案

使用指针跳过前缀字母字符，然后使用 strtol [ ^ ]将数字转换为长值。然后 endptr 变量将指向第一个非数字字符，允许您进一步解析。类似于：

  char  * strData =   * H1999999＃; 
  char  * strNum = strData +  2 ; 
  char  * strEnd = NULL; 
  long  lValue = strtol（strNum，& strEnd， 10 ）; 
  //   strEnd现在指向＃字符。 

I need some help in Identifying the string. I have incoming string like this

*H1999999#

it can vary from

*H1000000#~*H1999999#

sometimes it is

*H1FINE# or *H1MED#

or any other text in between.Now what I have already done is I have parsed the numeric string and copied the integer value to a buffer. Here is the code for that.

 char H1subbuff[10];
 char head1[4];
 char Initial[2];

 char *ptr;

 memcpy(Initial, &rec[0], 1 );
 Initial[1] = '\0';

 memcpy(head1, &rec[0], 3 );
 head1[3] = '\0';



 if ((strcmp(head1,"*H1") == 0) && (rec[9] == '#'))
  {
     memcpy(H1subbuff, &rec[3], 6 );
     H1subbuff[6] = '\0';

     H1Val = strtol(H1subbuff, &ptr, 10);

     //Display H1VAL
}

Now my query is how can check if the String consist of Number or Alphabet.All I need to check if the Portion between *H1 and # is numeric or Alphabet, if it is a numeric I can use

strtol()

to copy the int value into an buffer. How can I copy the alphabet or text into an buffer?

Note :- The above two string doesn't have same string length.

What I have tried:

I have tried to copy numeric values to a buffer.

解决方案

Use a pointer to skip the prefix alphabetic characters, then use strtol[^] to convert the number to a long value. The endptr variable will then point to the first non-numeric character, allowing you to parse further. Something like:

char* strData = "*H1999999#";
char* strNum = strData + 2;
char* strEnd = NULL;
long lValue = strtol(strNum, &strEnd, 10);
// strEnd will now point to the # character.

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