How to compare two strings and their upper and lower case signs

Question

Let\'s say I have 2 strings.First string is x = \"abc\" and the second one is y = \"ABC\".When I write in c# following code:

if(x == y)

or

Answer 1

The return value is not true but false since .NET is case sensitive by default.

From String.Equals:

This method performs an ordinal (case-sensitive and culture-insensitive) comparison.

For == the same is true since String.Equality operator calls Equals:

This operator is implemented using the Equals method, which means the comparands are tested for a combination of reference and value equality. This operator performs an ordinal comparison.

This will compare case insensitively:

bool equals = x.Equals(y , StringComparison.OrdinalIgnoreCase);

If you just want to know if a character is upper or lower case you can use these methods:

bool isUpperChar = Char.IsUpper("ABC"[0]); // yes
bool isLowerChar = Char.IsLower("ABC"[0]); // no