按索引获取字符串字符 - Java [英] Get string character by index - Java

问题描述

我知道如何计算字符串中某个字符或数字的索引，但是有没有什么预定义的方法可以用来给我在 nth 位置的字符?因此，在字符串foo"中，如果我要求索引为 0 的字符，它将返回f".

I know how to work out the index of a certain character or number in a string, but is there any predefined method I can use to give me the character at the nth position? So in the string "foo", if I asked for the character with index 0 it would return "f".

注意 - 在上面的问题中，字符"不是指 char 数据类型，而是指字符串中的字母或数字.这里重要的是，调用该方法时我没有收到一个字符，而是一个字符串(长度为 1).我知道 substring() 方法，但我想知道是否有更简洁的方法.

Note - in the above question, by "character" I don't mean the char data type, but a letter or number in a string. The important thing here is that I don't receive a char when the method is invoked, but a string (of length 1). And I know about the substring() method, but I was wondering if there was a neater way.

推荐答案

您正在寻找的方法是 charAt.举个例子:

The method you're looking for is charAt. Here's an example:

String text = "foo";
char charAtZero = text.charAt(0);
System.out.println(charAtZero); // Prints f

有关更多信息，请参阅关于 String.charAt 的 Java 文档.如果你想要另一个简单的教程，这个或这个.

For more information, see the Java documentation on String.charAt. If you want another simple tutorial, this one or this one.

如果您不想将结果作为 char 数据类型，而是作为字符串，您可以使用 Character.toString 方法:

If you don't want the result as a char data type, but rather as a string, you would use the Character.toString method:

String text = "foo";
String letter = Character.toString(text.charAt(0));
System.out.println(letter); // Prints f

如果您想了解有关 Character 类和 toString 方法的更多信息，我从 有关 Character.toString 的文档.

If you want more information on the Character class and the toString method, I pulled my info from the documentation on Character.toString.

这篇关于按索引获取字符串字符 - Java的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！