Swift String contains()

var message = "This is Swift Programming"

// check if message contains "Swift"
var result = message.contains("Swift")

print(result)

// Output: true

contains() Syntax

The syntax of the String contains() method is:

string.contains(char: charSequence)

Here, string is an object of the String class.

contains() Parameters

The contains() method takes a single parameter.

• char (charSequence) - a sequence of characters

contains() Return Values

contains() returns

• true - if the string contains the specified character sequence
• false - if the string doesn't contain the specified character sequence

Example 1: Swift String contains()

var message = "Swift Programming Language"

// check if message contains "Swift"
var result = message.contains("Swift")
print(result)      // true

// check if message contains "Java"
result = message.contains("Java")
print(result)      // false

// check if message contains " "
result = message.contains(" ");
print(result)      // true

Output

true
false
true

Here, message.contains(" ") returns true because the empty string is a subset of every other string.

Example 2: Using contains() With if...else

var message  = "Swift Programming Language"
var msg1 = "Swift"
var msg2 = "swift"
  
// true because message contains "Swift"
if (message.contains(msg1)) {

  print(message + " contains " + msg1)
}

else {

  print(message + " doesn't contain " + msg1)
}
  
// contains() is case-sensitive
// false because message doesn't contains "swift"
if (message.contains(msg2)) {

  print(message + " contains " + msg2)
}
else {

  print(message + " doesn't contain " + msg2)
}

Output

Swift Programming Language contains Swift
Swift Programming Language doesn't contain swift