0x00 Lesson

We’ve used lots of strings so far, and it turns out they are structs - they have their own methods and properties we can use to query and manipulate the string.

First, let’s create a test string:

let string = "Do or do not, there is no try."

You can read the number of characters in a string using its count property:

print(string. count)

They have a hasPrefix() method that returns true if the string starts with specific letters:

print(string.hasPrefix("Do"))

You can uppercase a string by calling its uppercased() method:

print(string.uppercased())

And you can even have Swift sort the letters of the string into an array:

print(string.sorted())

Strings have lots more properties and methods - try typin string. to bring up Xcode’s code completion options.

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