提问人:Emre 提问时间:2/28/2022 更新时间:2/28/2022 访问量:80
构造函数 [closed] 中未赋值的 ref 值
Unassigned ref value in the constructor [closed]
问:
我想在此代码中使用 ref 构造函数创建对象后,将 Data 类的输出值分配给 State 类。我该如何解决这个问题?
class Program
{
static void Main(string[] args)
{
Data data = new Data();
State stateA = new State("A", ref data.outputA);
State stateB = new State("B", ref data.outputB);
stateA.output = 10;
stateB.output = 8;
Console.WriteLine(data.outputA); //10
Console.WriteLine(data.outputB); //8
Console.ReadLine();
}
}
public class Data
{
public int outputA;
public int outputB;
}
public class State
{
public string name;
public ref int address;
public State(string _name, ref int _output)
{
this.name = _name;
address = _output;
}
}
答:
0赞
Federico Alterio
2/28/2022
#1
在 c# 中,ref 关键字与类似 C 的指针的概念相去甚远。这是您可以在该方向上执行的最接近的事情(使用安全代码):
class Program
{
static void Main(string[] args)
{
Data data = new Data();
State stateA = new State("A", value => data.outputA = value, () => data.outputA);
State stateB = new State("B", value => data.outputB = value, () => data.outputB);
stateA.Output = 10;
stateB.Output = 8;
Console.WriteLine(data.outputA); //10
Console.WriteLine(data.outputB); //8
Console.ReadLine();
}
}
public class Data
{
public int outputA;
public int outputB;
}
public class State
{
public string name;
private Action<int> _outputSetter;
private Func<int> _outputGetter;
public State(string _name, Action<int> _outputSetter, Func<int> _outputGetter)
{
this.name = _name;
this._outputSetter = _outputSetter;
this._outputGetter = _outputGetter;
}
public int Output
{
get => _outputGetter();
set => _outputSetter(value);
}
}
0赞
Serge
2/28/2022
#2
你将不得不稍微纠正一下状态类
Data data = new Data();
State stateA = new State("A", ref data);
State stateB = new State("B", ref data);
stateA.output = 10;
stateB.output = 8;
Console.WriteLine(data.outputA); //10
Console.WriteLine(data.outputB); //8
Console.ReadLine();
public class State
{
public int output
{
get { return name == "A" ? address.outputA : address.outputB; }
set { if(name == "A") address.outputA = value; else address.outputB = value; }
}
public string name;
public Data address;
public State(string _name, ref Data _output)
{
this.name = _name;
address = _output;
}
}
评论
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