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
Swift 5，不区分大小写:
如果string.localizedLowercase.contains(“迅速”.localizedLowercase) {
其他回答
给你:
let s = "hello Swift"
if let textRange = s.rangeOfString("Swift") {
NSLog("exists")
}
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
有了swift 4的新语法，你就可以
字符串。包含(“Swift 4是最好的”)
String是你的字符串变量
扩展的方法
斯威夫特4
extension String {
func contains(find: String) -> Bool{
return self.range(of: find) != nil
}
func containsIgnoringCase(find: String) -> Bool{
return self.range(of: find, options: .caseInsensitive) != nil
}
}
var value = "Hello world"
print(value.contains("Hello")) // true
print(value.contains("bo")) // false
print(value.containsIgnoringCase(find: "hello")) // true
print(value.containsIgnoringCase(find: "Hello")) // true
print(value.containsIgnoringCase(find: "bo")) // false
通常Swift 4有包含方法，但它可从iOS 8.0+
斯威夫特3.1
你可以为字符串写扩展contains:和containsIgnoringCase
extension String {
func contains(_ find: String) -> Bool{
return self.range(of: find) != nil
}
func containsIgnoringCase(_ find: String) -> Bool{
return self.range(of: find, options: .caseInsensitive) != nil
}
}
旧Swift版本
extension String {
func contains(find: String) -> Bool{
return self.rangeOfString(find) != nil
}
func containsIgnoringCase(find: String) -> Bool{
return self.rangeOfString(find, options: NSStringCompareOptions.CaseInsensitiveSearch) != nil
}
}
例子:
var value = "Hello world"
print(value.contains("Hello")) // true
print(value.contains("bo")) // false
print(value.containsIgnoringCase("hello")) // true
print(value.containsIgnoringCase("Hello")) // true
print(value.containsIgnoringCase("bo")) // false
>在swift 3.0
let str = "Hello Swift"
if str.lowercased().contains("Swift".lowercased()) {
print("String Contains Another String")
} else {
print("Not Exists")
}
输出
String Contains Another String
