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Strings

String.indexOf()

Find a substring inside a string. It returns the index of where the substring starts in the string, or -1 if the substring isn’t found. It’s case-sensitive.

let str = 'I love Cape Cod potato chips.';

// Returns 7
str.indexOf('Cape Cod');

// Returns 7
str.indexOf('Cape C');

// Returns -1
str.indexOf('cape cod');