For-in 循环需要“[UserVehicles]”遵守“顺序”；你的意思是打开可选的吗迅速

Swift
struct UserVehicles {
    let brand: String
    let model: String
}
let vehicles: [UserVehicles]? = [UserVehicles(brand: "BMW", model: "X5"), UserVehicles(brand: "Tesla", model: "Model 3")]
if let unwrappedVehicles = vehicles {
    for vehicle in unwrappedVehicles {
        print("Brand: \(vehicle.brand), Model: \(vehicle.model)")
    }
}

Swift
let vehicles: [UserVehicles]? = [UserVehicles(brand: "BMW", model: "X5"), UserVehicles(brand: "Tesla", model: "Model 3")]
for vehicle in vehicles { // 编译错误：Value of optional type '[UserVehicles]?' must be unwrapped to a value of type '[UserVehicles]'
    print("Brand: \(vehicle.brand), Model: \(vehicle.model)")
}