Question

在重复模式下检查每种类型的结构时遇到问题。

private static MyStruct myStruct;

public Form1()
{
    InitializeComponent();

    myStruct = new MyStruct[3]

    myStruct[0].OptionType = OptionType.Type00;
    myStruct[0].Type.Type00.Value00 = 5;
    myStruct[0].Type.Type00.Value01 = 10;

    myStruct[1].OptionType = OptionType.Type01;
    myStruct[1].Type.Type01.Value00 = 4;
    myStruct[1].Type.Type01.Value01 = 8;

    myStruct[2].Type.OptionType = OptionType.Type01;
    myStruct[2].Type.Type01.Value00 = 6;
    myStruct[2].Type.Type01.Value01 = 3;
}

private void btnClick_Click(object sender, EventArgs e)
{
    for (int i = 0; i < myStruct.Length; i++)
    {
        switch (myStruct[i].OptionType)
        {
            case OptionType.Type00:
            Console.WriteLine($"Value00 = {myStruct[i].Type.Type00.Value00} Value01 = {myStruct[i].Type.Type00.Value01}");
            break;
            case OptionType.Type01:
            Console.WriteLine($"Value00 = {myStruct[i].Type.Type01.Value00} Value01 = {myStruct[i].Type.Type01.Value01}");
            break;
        }
            //error
            //if (i == 2)
                //i = 0; //Repeat.

            //solution
            if (i == 2)
                i = -1; //Repeat.
    }
}

[StructLayout(LayoutKind.Sequential)]
public struct MyStruct
{
    internal OptionType OptionType;
    internal Type Type;
}

[StructLayout(LayoutKind.Explicit)]
internal struct Type
{
    [FieldOffset(0)]
    internal Type00 Type00;
    [FieldOffset(0)]
    internal Type01 Type01;
}

[Flags]
internal enum OptionType : uint
{
    Type00 = 0,
    Type01 = 1,
}

[StructLayout(LayoutKind.Sequential)]
internal struct Type00
{
    internal int Value00;
    internal int Value01;
}

[StructLayout(LayoutKind.Sequential)]
internal struct Type01
{
    internal int Value00;
    internal int Value01;
}

1°输出：

Value00 = 5，Value01 = 10;

Value00 = 4，Value01 = 8;

Value00 = 6，Value01 = 3;

2°，3°...重复输出：

Value00 = 4，Value01 = 8;

Value00 = 6，Value01 = 3;

在

myStruct[0].Type.Type00.Value00 and myStruct[0].Type.Type00.Value01

传递的值保持不变。

但是在

myStruct[0].OptionType, the passed value of OptionType.Type00

更改为OptionType.Type01;

为什么会发生？我们如何使其保持与以前相同的价值？

Answer 1

该示例代码重复两次，因为您将i设置为0，然后通过for循环将其递增为1，因此跳过了数组中的第一个元素。如果它实际上是在更改OptionType的值，它仍会打印一行，只是两个值均为0。

C＃如何将枚举类型保存到结构数组中的每个结构

1 个答案: