最简单的方法是绘制图像：

func renderImage(_ attributedString: NSAttributedString, for width: CGFloat) -> UIImage? {
    let boundingRect = attributedString.boundingRect(with: CGSize(width: width, height: .infinity), options: [.usesLineFragmentOrigin], context: nil)
    UIGraphicsBeginImageContextWithOptions(boundingRect.size, false, 0)
    attributedString.draw(in: CGRect(origin: .zero, size: boundingRect.size))
    let image = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()
    
    return image

然后将其与Image（）一起使用

if let image = renderImage(longText, for: geometry.size.width) {
          Image(uiImage: image)
        }

在最新的swiftUI中，您可以使用AttributedString代替NSAttributedString。
有关如何使用它的详细信息，请参阅Apple文档：https://developer.apple.com/documentation/foundation/attributedstring
但在 Package 原始NSTextField（macos）/ UITextField（IOS）控件的情况下，您仍然可以在swiftUI应用程序中使用NSAttributedString
macos Package 器示例（必须易于重写）：

import SwiftUI
import Cocoa

@available(OSX 11.0, *)
public struct AttributedText: NSViewRepresentable {
    private let text: NSAttributedString
    private let selectable: Bool
    
    public init(attributedString: NSAttributedString, selectable: Bool = true) {
        self.text = attributedString
        self.selectable = selectable
    }
    
    public func makeNSView(context: Context) -> NSTextField {
        let textField = NSTextField(labelWithAttributedString: text)
        textField.preferredMaxLayoutWidth = textField.frame.width
        textField.allowsEditingTextAttributes = true // Fix of clear of styles on click
        
        textField.isSelectable = selectable
        
        return textField
    }
    
    public func updateNSView(_ textField: NSTextField, context: Context) {
        textField.attributedStringValue = text
    }
}

但在大多数情况下，SwiftUI最好使用本地方式--AttributedString。