java.lang.String.indexOf(char
ch)
方法返回字符ch在指定字符串中第一次出现的下标索引位置
如果字符ch在指定的字符串中找不到,则返回-1
示例:
import java.lang.*;public class StringDemo {
public static void main(String[] args) {
String str = "This is tanglc‘s cnblog";
// returns the index of character s appear in the first time
System.out.println("index of letter ‘s‘ = "
+ str.indexOf(‘s‘));// returns -1 as character e is not in the string
System.out.println("index of letter ‘e‘ = "
+ str.indexOf(‘e‘));
}
}
运行结果:
index of letter ‘s‘ = 3
index of letter ‘e‘ = -1
时间: 2024-10-12 20:03:35