Java Replace Character At Specific Position Of String? [duplicate]

Question

I am trying to replace a character at a specific position of a string.

For example:

String str = "hi"; 

replace string position #2 (i) to another letter "k"

How would I do this? Thanks!

Answer 1

Petar Ivanov's answer to replace a character at a specific index in a string question

String are immutable in Java. You can't change them.

You need to create a new string with the character replaced.

String myName = "domanokz"; String newName = myName.substring(0,4)+'x'+myName.substring(5); 

Or you can use a StringBuilder:

StringBuilder myName = new StringBuilder("domanokz"); myName.setCharAt(4, 'x');  System.out.println(myName); 

Answer 2

Kay!

First of all, when dealing with strings you have to refer to their positions in 0 base convention. This means that if you have a string like this:

String str = "hi"; //str length is equal 2 but the character //'h' is in the position 0 and character 'i' is in the postion 1 

With that in mind, the best way to tackle this problem is creating a method to replace a character at a given position in a string like this:

Method:

public String changeCharInPosition(int position, char ch, String str){     char[] charArray = str.toCharArray();     charArray[position] = ch;     return new String(charArray); } 

Then you should call the method 'changeCharInPosition' in this way:

String str = "hi"; str = changeCharInPosition(1, 'k', str); System.out.print(str); //this will return "hk" 

If you have any questions, don't hesitate, post something!