public static void main(String[] args) { String str = "Hello, World!"; char ch = str.charAt(4); System.out.println(ch); // Output: o } } 在这个例子中,我们创建了一个字符串`"Hello, World!"`,然后调用了`charAt()`方法来获取该字符串中位置为4的字符,即`o`。最后,使用`System.out.p...
String str = "Hello, World!"; char ch = str.charAt(0); // 获取第一个字符 ch = Character.toUpperCase(ch); // 将其转换为大写 System.out.println("First character in uppercase: " + ch); 复制代码 然而,charAt() 函数也有一些限制: 索引越界:如果传递给 charAt() 函数的索引超出了字符串的...
1. 通过charAt获取第三个字符 char cabinNum2 = cabinNum.charAt(2); 1. 完整示例代码 for (FlightResult flightResult : book.getFlightResult()) { if (flightResult.getCabinString().contains(flightResult.getDefaultCabin().getCabinCode())) { if(flightResult.getCabinString().substring(flightResult....
这段代码为字母表中的每个字母创建了一个类似直方图的计数器。尝试打印字符，如'a'，如下所示：
charAt(int index) description of charAt returns char value at the specified index of string. example of charAt in java package lang; public class Lang { public static void main(String[] args) { String str = "test 1234";
out.println("The fifth character is: " + fifthChar); // 获取索引为-1的字符(这将抛出StringIndexOutOfBoundsException异常) char invalidChar = str.charAt(-1); } } 复制代码 输出: The first character is: H The fifth character is: o Exception in thread "main" java.lang.StringIndexOutOf...
Stringstr="howtodoinjava.com";Assertions.assertEquals('h',str.charAt(0)); To get the last character of theString, use theString.length()and subtract 1 to get the last valid index in the string. Assertions.assertEquals('m',str.charAt(str.length()-1)); ...
Java String.charAt() returns the character at specified index argument in the string object or literal. The argument must be a valid index.
Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of range: -1 at java.base/java.lang.StringLatin1.charAt(StringLatin1.java:48) at java.base/java.lang.String.charAt(String.java:1515) 1. 2. 3. ...
修改为：for(int i=length-1;i>=0;i--){ char ch = line.charAt(i);if(ch.equals(' ')){ System.out.println();} System.out.print(ch);} 是不是你想要的结果，