Java String.compareToIgnoreCase() method for Case insensitive string comparison by converting strings to their Unicode values

String.compareToIgnoreCase() Returns the difference. If both string are equal then 0 is returned.
Syntax

String1.compareToIgnoreCase(String2)

The output is an integer and the value is here

< 0 : If String1 is less than String2
= 0 : If String1 is equal to String2
< 1 : If String1 is greater than String2

Here are some examples with output.

String my_str1="Welcome to plus2net";
System.out.println(my_str1.compareToIgnoreCase("welcome to plus2net")); // 0

Note : Unicode value of W is 87 and lower case w is 119 ( difference is -32 ) . As this is case insensitive string comparison the output is 0.

The string comparision is done lexicographically ( dictionary order and alphabetical order ).

String my_str1="plus2net";
System.out.println(my_str1.compareToIgnoreCase("welcome")); // -7

Difference between unicode values of p and w is -7.

All String functions

compareTo() codePointCount() codePointAt() codePointBefore() Java - Tutorials

string.compareToIgnoreCase()

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