c# 我应该在 void 方法中使用输出吗？

Question

 private void button1_Click(object sender, EventArgs e)
    {
        try
        {
            int Number = Convert.ToInt32(textBox1.Text);
            HalfNumber(Number);
            textBox1.Focus();
            textBox1.SelectAll();
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
    }
    private void HalfNumber(int numberToUse)
    {
        double x = numberToUse / 2.0;
        MessageBox.Show("Half of the number is " + x.ToString());
    }
}
}

上面的代码是一个例子。
我以为我的导师说过永远不要在方法中使用输出，因为在测试代码的情况下，代码可能在世界的另一端，无法看到发生了什么。
我可能误会了她，但我希望有人解释一下

Answer 1

很难准确理解她的意思。然而，将对话框放在执行离散操作的函数中是出乎意料的。

return 来自 HalfNumber 方法的一个数字，然后显示包含结果的对话框会更合乎逻辑

private void button1_Click(object sender, EventArgs e)
{
    try
    {
        int Number = Convert.ToInt32(textBox1.Text);
        double myHalfNumber = HalfNumber(Number);

        MessageBox.Show("Half of the number is " +myHalfNumber.ToString());

        textBox1.Focus();
        textBox1.SelectAll();

    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.Message);
    }

}

private double HalfNumber(int numberToUse)
{      
    return numberToUse / 2.0;
}

关注点分离

In software engineering, Separation of Concerns refers to the delineation and correlation of software elements to achieve order within a system. Through proper separation of concerns, complexity becomes manageable

不要重复自己（干）

A principle of software development aimed at reducing repetition of software patterns, replacing them with abstractions; and several copies of the same data, using data normalization to avoid redundancy.

将 HalfNumber 放入它自己的离散方法中可以让您重用您的代码，并将逻辑分离为仅可维护和可预测的逻辑

Answer 2

void 表示您不能 return 任何值。如果你想输出你需要指定它。之后，您可以使用 return 值。

例如：

private double HalfNumber(int numberToUse)
{
    double x = numberToUse / 2.0;
    return x;
}

你可以这样使用

private void button1_Click(object sender, EventArgs e)
{
    try
    {
        int Number = Convert.ToInt32(textBox1.Text);
        double result = HalfNumber(Number);

        MessageBox.Show("Half of the number is " + result.ToString());
        textBox1.Focus();
        textBox1.SelectAll();
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.Message);
    }
}

private double HalfNumber(int numberToUse)
{
    double x = numberToUse / 2.0;
    return x;
}

c# 我应该在 void 方法中使用输出吗？

c# Should I use a output in my void method?

c#

methods

void

output