Android如何获取字符串的第一个字符？

Question

如何获得字符串的第一个字符？

string test = "StackOverflow";

第一个字符="S"

Answer 1

String test = "StackOverflow"; 
char first = test.charAt(0);

Answer 2

另一种方式是

String test = "StackOverflow";
String s=test.substring(0,1);

在这,你得到了结果 String

Answer 3

您可以参考此链接，第 4 点。

public class StrDemo
{
public static void main (String args[])
{
    String abc = "abc";

    System.out.println ("Char at offset 0 : " + abc.charAt(0) );
    System.out.println ("Char at offset 1 : " + abc.charAt(1) );
    System.out.println ("Char at offset 2 : " + abc.charAt(2) );

  //Also substring method
   System.out.println(abc.substring(1, 2));
   //it will print 

公元前

// as starting index to end index here in this case abc is the string 
   //at 0 index-a, 1-index-b, 2- index-c

// This line should throw a StringIndexOutOfBoundsException
    System.out.println ("Char at offset 3 : " + abc.charAt(3) );
 }
}