Swift--Define an empty string Hasprefix hassuffix trim split join range

Define an empty string

var str1 = ""

var str2 = String ()

Str1.isempty//Judging if the string is empty

All characters in the output string

var str3 = "As God name"

For C in str3{

println (c)

}

Maximum value of type int.max//int

Minimum value of type int.min//int

var arr1 = ["C", "OC", "ios", "Swift"]

var count = 0

For name in arr1{

If Name.hasprefix ("I") {//Hasprefix prefix

count++

Count

}

}

Count = 0

For name in arr1{

If Name.hassuffix ("s") {//Hassuffix suffix

count++

Count

}

}

var string1:string = "Hello, swift!!"

var string2 = "As God name"

Uppercasestring lowercasestring

String2.uppercasestring

String2.lowercasestring

Trim removes whitespace before and after a string

String1.stringbytrimmingcharactersinset (Nscharacterset.whitespaceandnewlinecharacterset ())

String1.stringbytrimmingcharactersinset (Nscharacterset (charactersinstring: "H"))

Split

String2.componentsseparatedbystring ("")

var string3 = "Welcome to play swift! Step-by-Step learn from Now "

String3.componentsseparatedbycharactersinset (Nscharacterset (charactersinstring: "-"))

Join

var String4 = "-"

String4.join (["One", "one", "one", "three"])

var string5 = "--"

var arr = ["ios", "Swift", "OC"]

String5.join (arr)

var str = "Welcome to play swift! Step by step Learn Swift language

Range

Str.rangeofstring ("Step")

Str.rangeofstring ("Step", Options:NSStringCompareOptions.BackwardsSearch)

Str.rangeofstring ("Welcome", Options:NSStringCompareOptions.CaseInsensitiveSearch)

Str.startindex

Str.endindex

Countelements (str)

var str = "Hello, playground"

Let Strrange = range<string.index> (Start:str.startIndex, End:str.endIndex)

Swift--Define an empty string Hasprefix hassuffix trim split join range