islower() - C函數
C庫函數 int islower(int c)檢查傳遞的字符是否是小寫字母。
聲明
以下是islower()函數的聲明。
int islower(int c);
參數
- c -- 這是要檢查的字符。
返回值
這個函數如果c是一個小寫字母返回一個非零值(true),否則0(false)
實例
下面的例子顯示islower()函數的用法。
#include <stdio.h> #include <ctype.h> int main() { int var1 = 'Q'; int var2 = 'q'; int var3 = '3'; if( islower(var1) ) { printf("var1 = |%c| is lowercase character
", var1 ); } else { printf("var1 = |%c| is not lowercase character
", var1 ); } if( islower(var2) ) { printf("var2 = |%c| is lowercase character
", var2 ); } else { printf("var2 = |%c| is not lowercase character
", var2 ); } if( islower(var3) ) { printf("var3 = |%c| is lowercase character
", var3 ); } else { printf("var3 = |%c| is not lowercase character
", var3 ); } return(0); }
讓我們編譯和運行上面的程序,這將產生以下結果:
var1 = |Q| is not lowercase character
var2 = |q| is lowercase character
var3 = |3| is not lowercase character