NSClassFromString在OC中运行良好，但在Swift中崩溃

func createInstance(className: String) -> Any? {
    guard let classType = NSClassFromString(className) as? NSObject.Type else {
        return nil
    }
    let instance = classType.init()
    return instance
}

func callMethod(className: String, methodName: String) {
    guard let classType = NSClassFromString(className) as? NSObject.Type else {
        return
    }
    let instance = classType.init()
    let selector = Selector(methodName)
    if instance.responds(to: selector) {
        instance.perform(selector)
    }
}

// 使用示例
let className = "MyClass"
if let instance = createInstance(className: className) {
    print("Successfully created instance of \(className)")
} else {
    print("Failed to create instance of \(className)")
}

let methodName = "myMethod"
callMethod(className: className, methodName: methodName)