CharAt 函数

Question

How do I properly use the charAt function to retrieve the character of string that my user wants inputted? I keep getting an error surrounding my (parseInt) function.

  System.out.println("Choose an individual character to print out: ");
   int  number = 0;

   try
   {
    number = Integer.parseInt(input.nextInt());
   }
   catch (IOException E)
   {
    System.out.println(E);
   }
   String aString = input.next();
   char aChar = aString.charAt(number);
   System.out.println ("The character you chose to print out is: " + aChar );

Answer 1

Javadocs useful resource: http://docs.oracle.com/javase/7/docs/api/java/lang/String.html

The "charAt" method takes an "int" as a parameter. You tell it the index position in the string you want returned. Remember it is also zero based.

For for the following:

String string = "abc"
string.charAt(0).equals('a'); // true
string.charAt(1).equals('b'); // true
string.charAt(2).equals('c'); // true
string.charAt(3).equals('x'); // error, no index "3"