Question

我有textField，我想删除某个角色后的所有角色。

例如，如果我在textField中的内容是单词Orange，并且我想删除n之后的所有字符，我希望在删除后获取Ora。

如何删除Swift中字符串中某个字符后的所有字符？

由于

Answer 1

您可以将rangeOfString和substringToIndex用于其startIndex，如下所示：

Swift 2

let word = "orange"
if let index = word.rangeOfString("n")?.startIndex {
    print(word.substringToIndex(index))  // "ora"
}

Swift 3

let word = "orange"
if let index = word.range(of: "n")?.lowerBound {
    print(word.substring(to: index))  // "ora"
}

Swift 4

let word = "orange"
if let index = word.range(of: "n")?.lowerBound {
    let substring = word[..<index]                 // "ora"
    // or  let substring = word.prefix(upTo: index) // "ora"
    // (see picture below) Using the prefix(upTo:) method is equivalent to using a partial half-open range as the collection’s subscript. 
    // The subscript notation is preferred over prefix(upTo:).

    let string = String(substring)
    print(string)  // "ora"
}

Deserialize a Dictionary

Answer 2

你可以这样做：

guard let range = text.rangeOfString("Your String or Character here") else {
    return the text 
}

return text.substringToIndex(range.endIndex)
// depending on if you want to delete before a certain string, you would use range.startIndex

从Swift中的字符串中删除某个字符后面的所有字符

2 个答案: