在数组列表中搜索字符串（Java）

Question

I created a method which searches for a string in an array list, however I the problem is, if I search for a book it has to be the exactly how it was inputted into the array list.

eg if I type in "Harry Potter" as a book title and search for it, I have to put in "Harry Potter", I can't put "harry potter" or "HARRY POTTER"as it won't recognize it, i know there is something called ignore case but can't get it to work, or may have had it in the wrong place.

My code:

public void searchBook() {

    System.out.println("\n"+"Enter the title of the book you would like to search for: ");
    String search = input.nextLine();

    for (int i = 0; i < newBook.size(); i++) {

        // IF statement to check that any book in the array list equals what
        // the user has typed in
        if ( newBook.get(i).getTitle().equals(search)  ) {

            System.out.println(("Book ID: " + newBook.get(i).getBookID() + "  Title: " + newBook.get(i).getTitle()
                    + "    Author: " + newBook.get(i).getAuthor() + "  Genre: " + newBook.get(i).getGenre()
                    + "   Date registered: " + newBook.get(i).getDateReg() + "   Loan Status: "
                    + newBook.get(i).getLoan() + "    Number of times loaned: " + newBook.get(i).getNumOfLoans()));

        } else {

            System.out.println("No match was found");
        }

    } // end of for

}// end of method

Answer 1

Change

if (newBook.get(i).getTitle().equals(search)

to

if (newBook.get(i).getTitle().equalsIgnoreCase(search)

The equalsIgnoreCase performs a String comparison ignoring case.

Answer 2

use equalsIgnoreCase() instead of equals()

Read for documentation here

from javadoc,

Compares this String to another String, ignoring case considerations. Two strings are considered equal ignoring case if they are of the same length and corresponding characters in the two strings are equal ignoring case.

Answer 3

对于搜索contains方法更正确

if (newBook.get(i).getTitle().toLowerCase().contains(search.toLowerCase()))