C语言 isupper()用法及代码示例

C编程中的isupper()函数检查给定字符是否为大写。 isupper()函数在ctype.h头文件中定义。
用法:

int isupper ( int x );

例子：

Input:A
Output:Entered character is uppercase character
Input:a
Output:Entered character is not uppercase character
Input:1
Output:Entered character is not uppercase character

// C program to demonstrate 
// isupper() function 
#include <ctype.h> 
#include <stdio.h> 
int main() 
{ 
    char ch = 'A'; 
  
    // checking uppercase 
    if (isupper(ch)) 
        printf("\nEntered character is uppercase character"); 
    else
        printf("\nEntered character is not uppercase character"); 
}

输出：

Entered character is uppercase character

应用：C编程语言中的isupper()函数用于查找给定句子中存在的大写字母总数。
例：

Input:GEEKSFORGEEKS
Output:Number of upper case present in the sentence is:13
Input:GeeksFORGeeks
Output:Number of upper case present in the sentence is:5
Input:geeksforgeeks
Output:Number of upper case present in the sentence is:0

// C program to demonstrate 
// isupper() function 
  
#include <ctype.h> 
#include <stdio.h> 
  
// called function 
int ttl_upper(int i, int counter) 
{ 
    char ch; 
    char a[50] = "GeeksForGeeks"; 
    ch = a[0]; 
  
    // counting of upper case 
    while (ch != '\0') { 
        ch = a[i]; 
        if (isupper(ch)) 
            counter++; 
  
        i++; 
    } 
  
    // returning total number of upper case present in sentence 
    return (counter); 
} 
int main() 
{ 
    int i = 0; 
    int counter = 0; 
  
    // calling function 
    counter = ttl_upper(i, counter); 
    printf("\nNumber of upper case present in the sentence is:%d", counter); 
    return 0; 
}

输出：

Number of upper case present in the sentence is:3

相关用法

注：本文由纯净天空筛选整理自Kanchan_Ray大神的英文原创作品 isupper() function in C Language。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。