Swift 文字列

文字列の入れ替え

let str:String = "abcdefghi"
println(str.stringByReplacingOccurrencesOfString("b", withString: "B", options: nil, range: nil)) 
// aBcdfghi

文字の数

let codeString = "test"
count(codeString.utf16) // 4

正規表現

• 正規表現の勉強や試すができるサイト　http://regexr.com/
• 置き換え

let textString = "http://www.test.jp/page"
var regVersion = textString.stringByReplacingOccurrencesOfString("http://([a-zA-Z0-9]|.|)+/", withString: "$1", options: NSStringCompareOptions.RegularExpressionSearch, range: nil)
// page

• 抽出

let textString = "http://www.test.jp/page"
let patternStr = "http://([a-zA-Z0-9]|.)+/"
let nsText = textString as NSString

let regex = NSRegularExpression(pattern: patternStr, options: NSRegularExpressionOptions.CaseInsensitive, error: nil)
let results = regex!.matchesInString(textString, options: NSMatchingOptions.allZeros, range: NSMakeRange(0, nsText.length))
let url = results.map {nsText.substringWithRange($0.range)}
print(url[0]) // http://www.test.jp/

文字列があるかどうか

let url = "http://www.test.jp"
if let range = url.rangeOfString("http") {
   return true
} else {
   return false
}