在Objective-C中，检查NSString子字符串的代码是:
NSString *string = @"hello Swift";
NSRange textRange =[string rangeOfString:@"Swift"];
if(textRange.location != NSNotFound)
{
NSLog(@"exists");
}
但是如何在Swift中做到这一点呢?
当前回答
给你!准备Xcode 8和Swift 3。
import UIKit
let mString = "This is a String that contains something to search."
let stringToSearchUpperCase = "String"
let stringToSearchLowerCase = "string"
mString.contains(stringToSearchUpperCase) //true
mString.contains(stringToSearchLowerCase) //false
mString.lowercased().contains(stringToSearchUpperCase) //false
mString.lowercased().contains(stringToSearchLowerCase) //true
其他回答
另一个。支持大小写和变音符。
斯威夫特3.0
struct MyString {
static func contains(_ text: String, substring: String,
ignoreCase: Bool = true,
ignoreDiacritic: Bool = true) -> Bool {
var options = NSString.CompareOptions()
if ignoreCase { _ = options.insert(NSString.CompareOptions.caseInsensitive) }
if ignoreDiacritic { _ = options.insert(NSString.CompareOptions.diacriticInsensitive) }
return text.range(of: substring, options: options) != nil
}
}
使用
MyString.contains("Niels Bohr", substring: "Bohr") // true
iOS 9 +
iOS 9开始提供大小写和变音符不敏感功能。
if #available(iOS 9.0, *) {
"Für Elise".localizedStandardContains("fur") // true
}
在Swift 3中
if((a.range(of: b!, options: String.CompareOptions.caseInsensitive, range: nil, locale: nil)) != nil){
print("Done")
}
Swift 5，不区分大小写:
如果string.localizedLowercase.contains(“迅速”.localizedLowercase) {
检查它是否包含“Hello”
let s = "Hello World"
if s.rangeOfString("Hello") != nil {
print("Yes it contains 'Hello'")
}
这是我在快速操场上的第一次尝试。 我通过提供两个新函数(contains和containsIgnoreCase)来扩展String
extension String {
func contains(other: String) -> Bool{
var start = startIndex
do{
var subString = self[Range(start: start++, end: endIndex)]
if subString.hasPrefix(other){
return true
}
}while start != endIndex
return false
}
func containsIgnoreCase(other: String) -> Bool{
var start = startIndex
do{
var subString = self[Range(start: start++, end: endIndex)].lowercaseString
if subString.hasPrefix(other.lowercaseString){
return true
}
}while start != endIndex
return false
}
}
像这样使用它
var sentence = "This is a test sentence"
sentence.contains("this") //returns false
sentence.contains("This") //returns true
sentence.containsIgnoreCase("this") //returns true
"This is another test sentence".contains(" test ") //returns true
我欢迎任何反馈:)
