# # `contains()`

The contains method determines whether the collection contains a given item:

    const collection = collect({
      name: "Steven Gerrard",
      number: 8
    });

    collection.contains("name");
    //=> true

    collection.contains("age");
    //=> false

    collection.contains("Steven Gerrard");
    //=> true

You may also work with arrays

    const collection = collect([1, 2, 3]);

    collection.contains(3);
    //=> true

You may also pass a key / value pair to the contains method, which will determine if the given pair exists in the collection:

    const collection = collect({
      name: "Steven Gerrard",
      number: 8
    });

    collection.contains("name", "Steve Jobs");
    //=> false

Finally, you may also pass a callback to the contains method to perform your own truth test:

    const collection = collect([1, 2, 3, 4, 5]);

    collection.contains((value, key) => value > 5);

    //=> false

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