如何在 SwiftUI 中使用 Touch ID 和 Face ID?

1. 需要通过指纹，面容认证后才能打开 App

2. 添加配置

需要向 Info.plist 文件中添加一个配置，向用户说明为什么要访问
添加 Privacy - Face ID Usage Description
并为其赋予值 $(PRODUCT_NAME) need Touch Id or Face ID permission for app lock

3. Show me the code

//
//  SwiftUIView84.swift
//  bill2
//
//  Created by 朱洪苇 on 2023/7/22.
//

import SwiftUI
import LocalAuthentication

struct SwiftUIView84: View {
    @State private var isUnlocked = false
    
    func authenticate() {
        let context = LAContext()
        var error: NSError?
        // 检查是否可以进行生物特征认证
        if context.canEvaluatePolicy(.deviceOwnerAuthenticationWithBiometrics, error: &error) {
            // 有可能，所以继续使用它
            let reason = "We need to unlock your data."
            context.evaluatePolicy(.deviceOwnerAuthenticationWithBiometrics, localizedReason: reason) { success, authenticationError in
                // 身份验证现已完成
                DispatchQueue.main.async {
                    if success {
                        // authenticated successfully
                        self.isUnlocked = true
                        print("成功认证")
                    } else {
                        // there was a problem
                        self.isUnlocked = false
                        print("有个问题")
                    }
                }
            }
        } else {
            print("没有生物识别")
            // 没有生物识别
        }
    }

    var body: some View {
        VStack {
            if self.isUnlocked {
                Text("Unlocked")
                    .foregroundColor(.green)
            } else {
                Text("Locked")
                    .foregroundColor(.red)
            }
        }
        .font(.largeTitle)
        .onAppear(perform: authenticate)
    }
}

struct SwiftUIView84_Previews: PreviewProvider {
    static var previews: some View {
        SwiftUIView84()
    }
}