无法转换&#39;Range类型的值 <String.Index> &#39;（又名&#39;范围 <String.CharacterView.Index> &#39;）预期参数类型&#39;NSRange&#39;（又名&#39;_NSRange&#39;）

Question

我试图用属性String替换子字符串。 以下是我的代码。

let searchText = self.searchBar.text!
let name = item.firstName ?? ""
let idNo = "Employee Id. \(item.employeeId ?? "NA")"

if let range = name.range(of: searchText, options: String.CompareOptions.caseInsensitive, range: nil, locale: nil)
{
    let attributedSubString = NSAttributedString.init(string: name.substring(with: range), attributes: [NSFontAttributeName : UIFont.boldSystemFont(ofSize: 17)])
    let normalNameString = NSMutableAttributedString.init(string: name)
    normalNameString.mutableString.replacingCharacters(in: range, with: attributedSubString)
    cell.name.attributedText = normalNameString
}
else
{
    cell.name.text = name
}

我收到编译时错误：

“无法将'Range'类型的值（又称'Range'）转换为预期的参数类型'NSRange'（又名'_NSRange'）”。

我应该在这里改变什么？

Answer 1

您可以使用NSString和NSRange ，还需要更改此行normalNameString.mutableString.replacingCharacters(in: range, with: attributedSubString) 并使用此行代替 normalNameString.replaceCharacters(in: nsRange, with: attributedSubString)因为mutableString是NSMutableString，和replacingCharacters预计字符串，而不是NSAttributtedString

完整代码（针对Swift5进行了更新）

    let nsRange = NSString(string: name).range(of: searchText, options: String.CompareOptions.caseInsensitive)

    if nsRange.location != NSNotFound
    {
        let attributedSubString = NSAttributedString.init(string: NSString(string: name).substring(with: nsRange), attributes: [NSAttributedString.Key.font : UIFont.boldSystemFont(ofSize: 17)])
        let normalNameString = NSMutableAttributedString.init(string: name)
        normalNameString.replaceCharacters(in: nsRange, with: attributedSubString)
        cell.name.attributedText = normalNameString
    }
    else
    {
        cell.name.text = name
    }

Answer 2

请这样做，

第一，

extension String {

    func nsRange(from range: Range<String.Index>) -> NSRange {
        let from = range.lowerBound.samePosition(in: utf16)
        let to = range.upperBound.samePosition(in: utf16)
        return NSRange(location: utf16.distance(from: utf16.startIndex, to: from),
                       length: utf16.distance(from: from, to: to))
    }
}

之后你有一个标签和字符串，

private func setAttributedLabel() {

    let lableText = UILabel()

    let strTitle = "Basic string Double tap" // your main string
    let title:NSMutableAttributedString = NSMutableAttributedString(string: strTitle)

    // give attribute to basic string
    title.addAttributes([NSForegroundColorAttributeName:UIColor.blue ,NSFontAttributeName:UIFont.boldSystemFont(ofSize: 15)], range: NSRange.init(location: 0, length: title.length))
    lableText.attributedText = title

    // give attribute to your range string
    let rangeOfString = lableText.text?.range(of: "Double tap") // this string is subString of strTitle
    title.addAttributes([NSForegroundColorAttributeName:UIColor.gray,NSFontAttributeName:UIFont.systemFont(ofSize: 15)], range: strTitle.nsRange(from: rangeOfString!))
    lableText.attributedText = title

}

我希望它会有所帮助。

Answer 3

您必须使用Range<String.index> lowerBound和UpperBound位置值创建NSRange实例，如下所示。

let searchText = "Kiran"
let name = "Kiran Jasvanee"
let idNo = "Employee Id. \("24")"

if let range = name.range(of: searchText, options: String.CompareOptions.caseInsensitive, range: nil, locale: nil)
{
    let attributedSubString = NSAttributedString.init(string: name.substring(with: range), attributes: [NSFontAttributeName : UIFont.boldSystemFont(ofSize: 17)])
    let normalNameString = NSMutableAttributedString.init(string: name)

    let startPos = name.distance(from: searchText.characters.startIndex, to: range.lowerBound)
    let nsrange = NSMakeRange(startPos, searchText.characters.count)

    normalNameString.replaceCharacters(in: nsrange, with: attributedSubString)
    labelName.attributedText = normalNameString
}
else
{
    labelName.text = name
}  

add， self.searchBar.text! 而不是搜索searchtext constant的"Kiran" searchtext constant 和
添加item.firstName ?? "" 根据您的要求， item.firstName ?? ""而不是"Kiran Jasvanee" name constant 。

我在一个演示中尝试过它，我发布的代码工作正常，如下所示。 请检查。

如果name = "AKiranJasvanee"

如果name = "KiranJasvanee"

Answer 4

在Swift Range中不是NSRange类型。 在这里，您将通过Swift Range类型，其中包含NSRange ，这就是您遇到错误的原因。

一种解决方法是您可以将您的name为NSString以获取NSRange类型的范围，如下所示：

let range = (name as NSString).range(of: searchText, options: String.CompareOptions.caseInsensitive)

let subString = NSString(string: name).substring(with: range)
let attributedSubString = NSAttributedString.init(string:subString, attributes: [NSFontAttributeName : UIFont.boldSystemFont(ofSize: 17)])
let normalNameString = NSMutableAttributedString.init(string: name)
normalNameString.replaceCharacters(in: range, with: attributedSubString)