快速使用属性字符串使文本加粗

我有这样的字符串

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

现在text1说另一个字符串t 1。我可以替换文本，但不能将其加粗。我想将新字符串加粗t 1，这样最终输出将是：

@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，但是我想在Swift中完成。

提前致谢。

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：

这是在单个标签中结合使用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
    }
}

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)

要将其分配给标签时：

yourLabel.attributedText = attributedString

编辑/更新：Xcode 8.3.2•Swift 3.1

如果您了解HTML和CSS，则可以使用它轻松地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

如果您使用的是本地化字符串，则可能无法始终依靠粗体字符串作为句子的结尾。如果是这种情况，那么以下方法会很好地工作：

例如查询“ blah”与任何项目都不匹配

/* 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

我扩展了David West的一个很好的答案，以便您可以输入一个字符串并告诉您所有您想加粗的子字符串：

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
}

然后这样称呼它：

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!)

这将在给定的字符串中加粗所有要加粗的子字符串

这是我想出的最好方法。添加一个可以从任何地方调用的函数，然后将其添加到文件中，而无需使用诸如Constants.swift之类的类，然后在许多情况下，只需调用一行代码即可在任何字符串中嵌入单词：

进入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，您可以为任何UILabel调用以下一行代码：

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)

基于Jeremy Bader和David West的出色答案，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)

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")

两分钱...

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)
    }
}

接受Prajeet Shrestha在此线程中的响应为有效，我想使用Label（如果已知）和字体特征扩展他的解决方案。

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
    }
}

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 ”

超级简单的方法做到这一点。

    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

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
}

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)!
}

只需使用如下代码：

 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

快速的两个班轮4：

            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)

使用Swift 5.1NSAttributedString.Key代替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

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

改善Prajeet Shrestha的答案：-

您可以为NSMutableAttributedString做一个通用扩展，它涉及的代码更少。在这种情况下，我选择使用系统字体，但是您可以对其进行调整，以便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
        }
    }

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，在第二个参数中给出了粗体文本。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