在 swift 中使用属性字符串使文本加粗

Question

我有这样的字符串

var str = "@text1 this is good @text1"

现在将text1替换为另一个字符串，例如t 1 。 我可以替换文本，但无法将其加粗。 我想将新字符串t 1加粗，以便最终输出为：

@t 1这很好@t 1

我该怎么做？

我看到的所有示例都在 Objective-C 中，但我想在 Swift 中进行。

Answer 1

用法：

let label = UILabel()
label.attributedText =
    NSMutableAttributedString()
        .bold("Address: ")
        .normal(" Kathmandu, Nepal\n\n")
        .orangeHighlight(" Email: ")
        .blackHighlight(" prajeet.shrestha@gmail.com ")
        .bold("\n\nCopyright: ")
        .underlined(" All rights reserved. 2020.")

结果：

这是在单个标签中组合粗体和普通文本以及其他一些奖励方法的巧妙方法。

扩展：Swift 5. *

extension NSMutableAttributedString {
    var fontSize:CGFloat { return 14 }
    var boldFont:UIFont { return UIFont(name: "AvenirNext-Bold", size: fontSize) ?? UIFont.boldSystemFont(ofSize: fontSize) }
    var normalFont:UIFont { return UIFont(name: "AvenirNext-Regular", size: fontSize) ?? UIFont.systemFont(ofSize: fontSize)}
    
    func bold(_ value:String) -> NSMutableAttributedString {
        
        let attributes:[NSAttributedString.Key : Any] = [
            .font : boldFont
        ]
        
        self.append(NSAttributedString(string: value, attributes:attributes))
        return self
    }
    
    func normal(_ value:String) -> NSMutableAttributedString {
        
        let attributes:[NSAttributedString.Key : Any] = [
            .font : normalFont,
        ]
        
        self.append(NSAttributedString(string: value, attributes:attributes))
        return self
    }
    /* Other styling methods */
    func orangeHighlight(_ value:String) -> NSMutableAttributedString {
        
        let attributes:[NSAttributedString.Key : Any] = [
            .font :  normalFont,
            .foregroundColor : UIColor.white,
            .backgroundColor : UIColor.orange
        ]
        
        self.append(NSAttributedString(string: value, attributes:attributes))
        return self
    }
    
    func blackHighlight(_ value:String) -> NSMutableAttributedString {
        
        let attributes:[NSAttributedString.Key : Any] = [
            .font :  normalFont,
            .foregroundColor : UIColor.white,
            .backgroundColor : UIColor.black
            
        ]
        
        self.append(NSAttributedString(string: value, attributes:attributes))
        return self
    }
    
    func underlined(_ value:String) -> NSMutableAttributedString {
        
        let attributes:[NSAttributedString.Key : Any] = [
            .font :  normalFont,
            .underlineStyle : NSUnderlineStyle.single.rawValue
            
        ]
        
        self.append(NSAttributedString(string: value, attributes:attributes))
        return self
    }
}

注意：如果编译器缺少 UIFont/UIColor，请用 NSFont/NSColor 替换它们。

Answer 2

var normalText = "Hi am normal"

var boldText  = "And I am BOLD!"

var attributedString = NSMutableAttributedString(string:normalText)

var attrs = [NSFontAttributeName : UIFont.boldSystemFont(ofSize: 15)]
var boldString = NSMutableAttributedString(string: boldText, attributes:attrs)

attributedString.append(boldString)

当您想将其分配给标签时：

yourLabel.attributedText = attributedString

Answer 3

编辑/更新： Xcode 8.3.2 • Swift 3.1

如果您了解 HTML 和 CSS，您可以使用它轻松控制属性字符串的字体样式、颜色和大小，如下所示：

extension String {
    var html2AttStr: NSAttributedString? {
        return try? NSAttributedString(data: Data(utf8), options: [NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType, NSCharacterEncodingDocumentAttribute: String.Encoding.utf8.rawValue], documentAttributes: nil)
    }
}

"<style type=\"text/css\">#red{color:#F00}#green{color:#0F0}#blue{color: #00F; font-weight: Bold; font-size: 32}</style><span id=\"red\" >Red,</span><span id=\"green\" > Green </span><span id=\"blue\">and Blue</span>".html2AttStr

Answer 4

如果您使用本地化字符串，您可能无法依赖始终位于句子末尾的粗体字符串。 如果是这种情况，那么以下方法运行良好：

例如查询“blah”不匹配任何项目

/* Create the search query part of the text, e.g. "blah". 
   The variable 'text' is just the value entered by  the user. */
let searchQuery = "\"\(text)\""

/* Put the search text into the message */
let message = "Query \(searchQuery). does not match any items"

/* Find the position of the search string. Cast to NSString as we want
   range to be of type NSRange, not Swift's Range<Index> */
let range = (message as NSString).rangeOfString(searchQuery)

/* Make the text at the given range bold. Rather than hard-coding a text size,
   Use the text size configured in Interface Builder. */
let attributedString = NSMutableAttributedString(string: message)
attributedString.addAttribute(NSFontAttributeName, value: UIFont.boldSystemFontOfSize(label.font.pointSize), range: range)

/* Put the text in a label */
label.attributedText = attributedString

Answer 5

Swift 4 及更高版本

对于 Swift 4 及更高版本，这是一个好方法：

    let attributsBold = [NSAttributedString.Key.font : UIFont.systemFont(ofSize: 16, weight: .bold)]
    let attributsNormal = [NSAttributedString.Key.font : UIFont.systemFont(ofSize: 16, weight: .regular)]
    var attributedString = NSMutableAttributedString(string: "Hi ", attributes:attributsNormal)
    let boldStringPart = NSMutableAttributedString(string: "John", attributes:attributsBold)
    attributedString.append(boldStringPart)
  
    yourLabel.attributedText = attributedString

在标签中，文本看起来像：“嗨，约翰”

Answer 6

这是我想出的最好的方法。 添加一个您可以从任何地方调用的函数，并将其添加到一个没有像 Constants.swift 这样的类的文件中，然后您可以在任何字符串中添加单词，在很多情况下，只需调用一行代码：

进入一个 constants.swift 文件：

import Foundation
import UIKit

func addBoldText(fullString: NSString, boldPartOfString: NSString, font: UIFont!, boldFont: UIFont!) -> NSAttributedString {
   let nonBoldFontAttribute = [NSFontAttributeName:font!]
   let boldFontAttribute = [NSFontAttributeName:boldFont!]
   let boldString = NSMutableAttributedString(string: fullString as String, attributes:nonBoldFontAttribute)
   boldString.addAttributes(boldFontAttribute, range: fullString.rangeOfString(boldPartOfString as String))
   return boldString
}

然后你可以为任何 UILabel 调用这一行代码：

self.UILabel.attributedText = addBoldText("Check again in 30 DAYS to find more friends", boldPartOfString: "30 DAYS", font: normalFont!, boldFont: boldSearchFont!)


//Mark: Albeit that you've had to define these somewhere:

let normalFont = UIFont(name: "INSERT FONT NAME", size: 15)
let boldFont = UIFont(name: "INSERT BOLD FONT", size: 15)

Answer 7

我扩展了 David West 的精彩答案，以便您可以输入一个字符串并告诉它您想要加强的所有子字符串：

func addBoldText(fullString: NSString, boldPartsOfString: Array<NSString>, font: UIFont!, boldFont: UIFont!) -> NSAttributedString {
    let nonBoldFontAttribute = [NSFontAttributeName:font!]
    let boldFontAttribute = [NSFontAttributeName:boldFont!]
    let boldString = NSMutableAttributedString(string: fullString as String, attributes:nonBoldFontAttribute)
    for i in 0 ..< boldPartsOfString.count {
        boldString.addAttributes(boldFontAttribute, range: fullString.rangeOfString(boldPartsOfString[i] as String))
    }
    return boldString
}

然后像这样调用它：

let normalFont = UIFont(name: "Dosis-Medium", size: 18)
let boldSearchFont = UIFont(name: "Dosis-Bold", size: 18)
self.UILabel.attributedText = addBoldText("Check again in 30 days to find more friends", boldPartsOfString: ["Check", "30 days", "find", "friends"], font: normalFont!, boldFont: boldSearchFont!)

这将使您想要在给定字符串中加粗的所有子字符串更加大胆

Answer 8

基于 Jeremy Bader 和 David West 的出色回答，Swift 3 扩展：

extension String {
    func withBoldText(boldPartsOfString: Array<NSString>, font: UIFont!, boldFont: UIFont!) -> NSAttributedString {
        let nonBoldFontAttribute = [NSFontAttributeName:font!]
        let boldFontAttribute = [NSFontAttributeName:boldFont!]
        let boldString = NSMutableAttributedString(string: self as String, attributes:nonBoldFontAttribute)
        for i in 0 ..< boldPartsOfString.count {
            boldString.addAttributes(boldFontAttribute, range: (self as NSString).range(of: boldPartsOfString[i] as String))
        }
        return boldString
    }
}

用法：

let label = UILabel()
let font = UIFont(name: "AvenirNext-Italic", size: 24)!
let boldFont = UIFont(name: "AvenirNext-BoldItalic", size: 24)!
label.attributedText = "Make sure your face is\nbrightly and evenly lit".withBoldText(
    boldPartsOfString: ["brightly", "evenly"], font: font, boldFont: boldFont)

Answer 9

用法....

let attrString = NSMutableAttributedString()
            .appendWith(weight: .semibold, "almost bold")
            .appendWith(color: .white, weight: .bold, " white and bold")
            .appendWith(color: .black, ofSize: 18.0, " big black")

两分...

extension NSMutableAttributedString {

    @discardableResult func appendWith(color: UIColor = UIColor.darkText, weight: UIFont.Weight = .regular, ofSize: CGFloat = 12.0, _ text: String) -> NSMutableAttributedString{
        let attrText = NSAttributedString.makeWith(color: color, weight: weight, ofSize:ofSize, text)
        self.append(attrText)
        return self
    }

}
extension NSAttributedString {

    public static func makeWith(color: UIColor = UIColor.darkText, weight: UIFont.Weight = .regular, ofSize: CGFloat = 12.0, _ text: String) -> NSMutableAttributedString {

        let attrs = [NSAttributedStringKey.font: UIFont.systemFont(ofSize: ofSize, weight: weight), NSAttributedStringKey.foregroundColor: color]
        return NSMutableAttributedString(string: text, attributes:attrs)
    }
}

Answer 10

接受Prajeet Shrestha在此线程中的响应是有效的，如果已知 Label 和字体的特征，我想使用 Label 扩展他的解决方案。

斯威夫特 4

extension NSMutableAttributedString {

    @discardableResult func normal(_ text: String) -> NSMutableAttributedString {
        let normal = NSAttributedString(string: text)
        append(normal)

        return self
    }

    @discardableResult func bold(_ text: String, withLabel label: UILabel) -> NSMutableAttributedString {

        //generate the bold font
        var font: UIFont = UIFont(name: label.font.fontName , size: label.font.pointSize)!
        font = UIFont(descriptor: font.fontDescriptor.withSymbolicTraits(.traitBold) ?? font.fontDescriptor, size: font.pointSize)

        //generate attributes
        let attrs: [NSAttributedStringKey: Any] = [NSAttributedStringKey.font: font]
        let boldString = NSMutableAttributedString(string:text, attributes: attrs)

        //append the attributed text
        append(boldString)

        return self
    }
}

Answer 11

超级简单的方法来做到这一点。

    let text = "This string is having multiple font"
    let attributedText = 
    NSMutableAttributedString.getAttributedString(fromString: text)

    attributedText.apply(font: UIFont.boldSystemFont(ofSize: 24), subString: 
    "This")

    attributedText.apply(font: UIFont.boldSystemFont(ofSize: 24), onRange: 
    NSMakeRange(5, 6))

有关更多详细信息，请单击此处： https : //github.com/iOSTechHub/AttributedString

Answer 12

这可能有用

class func createAttributedStringFrom (string1 : String ,strin2 : String, attributes1 : Dictionary<String, NSObject>, attributes2 : Dictionary<String, NSObject>) -> NSAttributedString{

let fullStringNormal = (string1 + strin2) as NSString
let attributedFullString = NSMutableAttributedString(string: fullStringNormal as String)

attributedFullString.addAttributes(attributes1, range: fullStringNormal.rangeOfString(string1))
attributedFullString.addAttributes(attributes2, range: fullStringNormal.rangeOfString(strin2))
return attributedFullString
}

Answer 13

斯威夫特 3.0

根据您的要求将 html 转换为字符串和字体更改。

do {

     let str = try NSAttributedString(data: ("I'm a normal text and <b>this is my bold part . </b>And I'm again in the normal text".data(using: String.Encoding.unicode, allowLossyConversion: true)!), options: [ NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType], documentAttributes: nil)

     myLabel.attributedText = str
     myLabel.font =  MONTSERRAT_BOLD(23)
     myLabel.textAlignment = NSTextAlignment.left
} catch {
     print(error)
}

func MONTSERRAT_BOLD(_ size: CGFloat) -> UIFont
{
    return UIFont(name: "MONTSERRAT-BOLD", size: size)!
}

Answer 14

对于 -> 按尺寸搜索电视

1 路使用 NString 及其范围

let query = "Television"
let headerTitle = "size"
let message = "Search \(query) by \(headerTitle)"
let range = (message as NSString).range(of: query)
let attributedString = NSMutableAttributedString(string: message)
attributedString.addAttribute(NSAttributedString.Key.font, value: UIFont.boldSystemFont(ofSize: label1.font.pointSize), range: range)
label1.attributedText = attributedString

另一个不使用 NString 及其范围

let query = "Television"
let headerTitle = "size"
let (searchText, byText) = ("Search ", " by \(headerTitle)")
let attributedString = NSMutableAttributedString(string: searchText)
let byTextAttributedString = NSMutableAttributedString(string: byText)
let attrs = [NSAttributedString.Key.font : UIFont.boldSystemFont(ofSize: label1.font.pointSize)]
let boldString = NSMutableAttributedString(string: query, attributes:attrs)
attributedString.append(boldString)
attributedString.append(byTextAttributedString)
label1.attributedText = attributedString

迅捷5

Answer 15

用于制作混合类型字符串 (Attributed String) 如果文本是静态的，最好使用 Xcode 的界面构建器。 这非常容易和方便。

Answer 16

只需使用这样的代码：

 let font = UIFont(name: "Your-Font-Name", size: 10.0)!

        let attributedText = NSMutableAttributedString(attributedString: noteLabel.attributedText!)
        let boldedRange = NSRange(attributedText.string.range(of: "Note:")!, in: attributedText.string)
        attributedText.addAttributes([NSAttributedString.Key.font : font], range: boldedRange)
        noteLabel.attributedText = attributedText

Answer 17

swift 4 中的两个班轮：

            button.setAttributedTitle(.init(string: "My text", attributes: [.font: UIFont.systemFont(ofSize: 20, weight: .bold)]), for: .selected)
            button.setAttributedTitle(.init(string: "My text", attributes: [.font: UIFont.systemFont(ofSize: 20, weight: .regular)]), for: .normal)

Answer 18

Swift 5.1使用NSAttributedString.Key而不是NSAttributedStringKey

let test1Attributes:[NSAttributedString.Key: Any] = [.font : UIFont(name: "CircularStd-Book", size: 14)!]
let test2Attributes:[NSAttributedString.Key: Any] = [.font : UIFont(name: "CircularStd-Bold", size: 16)!]

let test1 = NSAttributedString(string: "\(greeting!) ", attributes:test1Attributes)
let test2 = NSAttributedString(string: firstName!, attributes:test2Attributes)
let text = NSMutableAttributedString()

text.append(test1)
text.append(test2)
return text

Answer 19

对于最新版本（iOS 15+），您可以使用AttributedString创建 Markdown 字符串：

let rawMarkdown = "This is **bold**"
let content;

do {
    content = try AttributedString(markdown: rawMarkdown)
} catch {
    content = AttributedString(rawMarkdown)
}

并使用 Swift UI 的Text显示它们：

Text(content)

Answer 20

改进 Prajeet Shrestha 的回答：-

你可以为 NSMutableAttributedString 做一个通用的扩展，它涉及的代码更少。 在这种情况下，我选择使用系统字体，但您可以对其进行调整，以便您可以输入字体名称作为参数。

    extension NSMutableAttributedString {

        func systemFontWith(text: String, size: CGFloat, weight: CGFloat) -> NSMutableAttributedString {
            let attributes: [String: AnyObject] = [NSFontAttributeName: UIFont.systemFont(ofSize: size, weight: weight)]
            let string = NSMutableAttributedString(string: text, attributes: attributes)
            self.append(string)
            return self
        }
    }

Answer 21

您可以使用下面编写的简单自定义方法来执行此操作。 您在第一个参数中给出了整个字符串，在第二个参数中将文本设为粗体。 希望这会有所帮助。

func getAttributedBoldString(str : String, boldTxt : String) -> NSMutableAttributedString {
        let attrStr = NSMutableAttributedString.init(string: str)
        let boldedRange = NSRange(str.range(of: boldTxt)!, in: str)
        attrStr.addAttributes([NSAttributedString.Key.font : UIFont.systemFont(ofSize: 17, weight: .bold)], range: boldedRange)
        return attrStr
    }

用法： initalString = 我是男孩

label.attributedText = getAttributedBoldString(str：initalString，boldTxt：“男孩”)

结果字符串 = 我是男孩