C library functions - isalpha ()
C standard library - <ctype.h>
description
C library functionsvoid isalpha (int c) Check preaching character is a letter.
statement
Here is () statement isalpha function.
int isalpha(int c);
parameter
- c - This was a test of character.
return value
If c is a letter, the function returns a nonzero value, otherwise return 0.
Examples
The following example demonstrates isalpha () function is used.
#include <stdio.h> #include <ctype.h> int main() { int var1 = 'd'; int var2 = '2'; int var3 = '\t'; int var4 = ' '; if( isalpha(var1) ) { printf("var1 = |%c| 是一个字母\n", var1 ); } else { printf("var1 = |%c| 不是一个字母\n", var1 ); } if( isalpha(var2) ) { printf("var2 = |%c| 是一个字母\n", var2 ); } else { printf("var2 = |%c| 不是一个字母\n", var2 ); } if( isalpha(var3) ) { printf("var3 = |%c| 是一个字母\n", var3 ); } else { printf("var3 = |%c| 不是一个字母\n", var3 ); } if( isalpha(var4) ) { printf("var4 = |%c| 是一个字母\n", var4 ); } else { printf("var4 = |%c| 不是一个字母\n", var4 ); } return(0); }
Let's compile and run the above program, which will result in the following:
var1 = |d| 是一个字母 var2 = |2| 不是一个字母 var3 = | | 不是一个字母 var4 = | | 不是一个字母