char c = str.charAt(i);什么意思

Question

import java.io.*;
public class A5{
public static void main(String[] args) throws IOException {
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("请输入一组字符串");
String str=br.readLine();
int countNum = 0;//统计数字的个数
int countChar = 0;//统计英文字母的个数
int countSpace = 0;//统计空格的个数
int countOthers = 0;//统计其它字符的个数
for (int i = 0; i < str.length(); i++) {
char c = str.charAt(i); //这句话是什么意思呀？？
if (c >= '0' && (int) c <= '9') {
countNum++;
} else if ((c >= 'a' && c <= 'z')||(c >= 'A' && c <= 'Z')) { countChar++;
} else if (c == ' ') {
countSpace++;
} else{
countOthers++;
}
}
System.out.println("数字个数:"+countNum);
System.out.println("英文字母个数:"+countChar);
System.out.println("空格个数:"+countSpace);
System.out.println("其他字符个数:"+countOthers);
}
}

Answer 1

字符串里的第i个字符啊 假设str ="abcd" char c = str.charAt(0) c值就是‘a'

Answer 2

把str的第i个char值赋值给c，类似于数组的挨个查找。本回答被提问者采纳