最近在做一个练习项目的时候，经常写到要设置富文本属性的地方，所以写了一个简单的封装，因为swift的字符下标采用的是string.index的类型，而富文本熟悉设置是原有的Range(Int, Int)类型。所以在将字符的string.index转为Int这方面耗费了不少功夫，最终也还是没有找到直接转换的方法。而是通过截取string.index的内容来获取相对应的Int下标。虽然是挺非主流的方法，但是本人亲测有效。另外如果你有更好的string.index转Int下标的方法，欢迎分享，当然是在swift3.0的环境下，哈哈。
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结果
屏幕快照 2017-03-23 下午1.50.01.png - 调用示例
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let lbl = UILabel.init(with: "", textColor: UIColor.black, fontSize: 15)
let originString = "周末闲着无聊，想起最近遇到一个关于文字显示设置的小问题，想着以后可能还会经常用到，所以趁这个时候一起整理一下，方便以后备用"
//初始化一个CHAttributeStringTool对象
let ch = CHAttributeStringTool.init(withString: originString)
//设置富文本属性，注：属性可以叠加，from：起始字符，传""表示从第一个字符；to：截止字符，传""表示到最后一个字符
ch.set(strikeLineColor: UIColor.red, lineSize: 5, from: "想着以后", to: "用到")
//赋值富文本属性
lbl.attributedText = ch.chString
lbl.frame = CGRect(x: (UIScreen.main.bounds.size.width - 200)/2, y: 100, width: 200, height: 300)
lbl.numberOfLines = 0
self.view.addSubview(lbl)
}
}
//MARK: - UIlabel
extension UILabel {
convenience init(with text: String, textColor: UIColor,fontSize: CGFloat) {
self.init()
self.text = text
self.font = UIFont.systemFont(ofSize: fontSize)
self.textColor = textColor
}
}
- 以下是封装代码，有用的话直接拷走就行啦，然后记得给个赞哈哈哈
import UIKit
class CHAttributeStringTool: NSObject {
//MARK: - 内部属性
private var originString: String?
private var characterCount: Int = 0
private var style = NSMutableParagraphStyle()
private var range: NSRange?
//MARK: - 外部属性
public var chString: NSMutableAttributedString?
//MARK: - 外部方法
init(withString str: String) {
originString = str
characterCount = str.characters.count
chString = NSMutableAttributedString.init(string: str)
}
///设置删除线
public func set(strikeLineColor lineColor: UIColor,lineSize: Float, from: String, to: String) {
let range = calculRange(withString: originString!, from: from, to: to)
chString?.addAttributes([NSStrikethroughStyleAttributeName: lineSize], range: range)
chString?.addAttributes([NSStrikethroughColorAttributeName: lineColor], range: range)
}
///设置下划线
public func set(underLineColor lineColor: UIColor, lineSize: Float, from: String, to: String) {
let range = calculRange(withString: originString!, from: from, to: to)
chString?.addAttributes([NSUnderlineStyleAttributeName: lineSize], range: range)
chString?.addAttributes([NSUnderlineColorAttributeName: lineColor], range: range)
}
///设置字体倾斜
public func set(Obliqueness size: CGFloat, from: String, to: String) {
let range = calculRange(withString: originString!, from: from, to: to)
chString?.addAttributes([NSObliquenessAttributeName: size], range: range)
}
///设置字距
public func set(stringSpacing: Float, from: String, to: String) {
let range = calculRange(withString: originString!, from: from, to: to)
chString?.addAttributes([NSKernAttributeName: stringSpacing], range: range)
}
///设置字号
public func set(fontSize: CGFloat, from: String, to: String) {
let range = calculRange(withString: originString!, from: from, to: to)
chString?.addAttributes([NSFontAttributeName: UIFont.systemFont(ofSize: fontSize)], range: range)
}
///设置粗体字号
public func set(boldFontSize: CGFloat, from: String, to: String) {
let range = calculRange(withString: originString!, from: from, to: to)
chString?.addAttributes([NSFontAttributeName: UIFont.boldSystemFont(ofSize: boldFontSize)], range: range)
}
///设置前景色
public func set(foregroundColor color: UIColor, from: String, to: String) {
let range = calculRange(withString: originString!, from: from, to: to)
chString?.addAttributes([NSForegroundColorAttributeName: color], range: range)
}
///设置背景色
public func set(backgroundColor color: UIColor, from: String, to: String) {
let range = calculRange(withString: originString!, from: from, to: to)
chString?.addAttributes([NSBackgroundColorAttributeName: color], range: range)
}
///段落属性相关
///设置行间距
public func set(lineSpacing: CGFloat) {
let range = calculRange(withString: originString!, from: "", to: "")
style.lineSpacing = lineSpacing
chString?.addAttributes([NSParagraphStyleAttributeName: style], range: range)
}
///设置首行缩进距离
public func set(firstLineIndent indent : CGFloat) {
let range = calculRange(withString: originString!, from: "", to: "")
style.firstLineHeadIndent = indent
chString?.addAttributes([NSParagraphStyleAttributeName: style], range: range)
}
///设置每行行首缩进距离
public func set(headerIndent indent: CGFloat) {
let range = calculRange(withString: originString!, from: "", to: "")
style.headIndent = indent
chString?.addAttributes([NSParagraphStyleAttributeName: style], range: range)
}
///设置每行行末缩进距离
public func set(tailIndent indent: CGFloat) {
let range = calculRange(withString: originString!, from: "", to: "")
style.tailIndent = -indent
chString?.addAttributes([NSParagraphStyleAttributeName: style], range: range)
}
///设置文本对齐
public func set(textAlignment alignment: NSTextAlignment) {
let range = calculRange(withString: originString!, from: "", to: "")
style.alignment = alignment
chString?.addAttributes([NSParagraphStyleAttributeName: style], range: range)
}
//MARK: - 内部方法
///计算range
private func calculRange(withString originStr:String, from: String, to: String)-> NSRange {
var loc1 = 0
var loc2 = 0
loc1 = from == "" ? 0 : stringIndexToInt(withString: originStr, calculString: from).start
loc2 = to == "" ? characterCount : stringIndexToInt(withString: originStr, calculString: to).end
return NSMakeRange(loc1, loc2 - loc1)
}
///string.index转Int
private func stringIndexToInt(withString originString: String, calculString: String)-> (start: Int, end: Int) {
let range = originString.range(of: calculString)
if range == nil {
print("originString中不包含calculString")
return (0,0)
}
let rangeStr = String(describing: range?.lowerBound)
print(rangeStr.characters)
let positionRange1 = rangeStr.range(of: "_position: ")
let positionRange2 = rangeStr.range(of: ")")
print(rangeStr)
let str = rangeStr.substring(with: ((positionRange1?.upperBound)!..<(positionRange2?.lowerBound)!))
let rangeStr2 = String.init(describing: range?.upperBound)
print(rangeStr2)
let positionRange3 = rangeStr2.range(of: "_position: ")
let positionRange4 = rangeStr2.range(of: ")")
let str2 = rangeStr2.substring(with: ((positionRange3?.upperBound)!..<(positionRange4?.lowerBound)!))
print(str2)
let result = (start: Int(str)!, end: Int(str2)!)
return result
}
}