如何更改字符串中“，”后面的字体

Question

我有一个包含金额的字符串值，其中我将小数部分指定为“，”之后，并且我想将“，”之后部分的字体更改为其他部分的一半

private func getText(text: String, size: CGFloat) -> NSAttributedString {
    let attributedString = NSMutableAttributedString(
        string: text,
        attributes: [
            .font: UIFont.themeFont(ofSize: size, weight: .medium)
        ]
    )
    
    if let commaRange = text.range(of: ",") {
        let startIndex = text.index(commaRange.upperBound, offsetBy: 1)
        let substring = text[startIndex...]
        
        attributedString.addAttributes(
            [
                .font: UIFont.themeFont(ofSize: size / 2, weight: .medium)
            ],
            range: NSRange(location: text.distance(from: text.startIndex, to: startIndex), length: substring.count)
        )
    }
    
    return attributedString
}

Answer 1

你需要更换

let startIndex = text.index(commaRange.upperBound, offsetBy: 1)

与

let startIndex = commaRange.upperBound 

这是一个测试演示

class ViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
        let bl = UILabel(frame: UIScreen.main.bounds)
        bl.attributedText = getText(text: "123323232333,454", size: 20)
        view.addSubview(bl)
    }
    private func getText(text: String, size: CGFloat) -> NSAttributedString {
        let attributedString = NSMutableAttributedString(
            string: text,
            attributes: [
                .font: UIFont.themeFont(ofSize: size, weight: .medium)
            ]
        )
        if let commaRange = text.range(of: ",") {
            let startIndex = commaRange.upperBound
            let substring = text[startIndex...]
            
            attributedString.addAttributes(
                [
                   .font: UIFont.themeFont(ofSize: size/2, weight: .medium)
                ],
                range: NSRange(location: text.distance(from: text.startIndex, to: startIndex), length: substring.count)
            )
        }
        return attributedString
    }
}