Question

是否可以从同一表单上的其他 private string 访问 private void 而不是其他表单？

private void english()
{
    string value1 = "Hello!";
}

private void button1_Click(object sender, EventArgs e)
{
    label1.Text = value1;
}

错误是：当前上下文中不存在名称“value1”

Answer 1

您正在尝试访问另一个方法中的局部变量。局部变量是在方法范围内声明的变量（在您的情况下 - 在方法english()中。这些变量只能从同一方法访问。

但是，你可以做的是在方法english()之外创建一个类字段，在这种情况下，它可以从这个类的任何非静态方法访问：

private string value1;
private void english()
{
    value1 = "Hello!";
}

private void button1_Click(object sender, EventArgs e)
{
    label1.Text = value1;
}

Answer 2

与上一个答案一样。范围定义了变量的可用位置。如果你是c＃的新手，范围可以被视为括号的“花哨名称”。

class Program
{
    private string _sPrivate; //This is a private variable, only accessable to methods within the class.
    public string PublicString; //This is a public variable, it is accessable outside the class.

    private void _privateMethod(string this_is_an_argument) //This is a method, since it is private, it is only available inside the above class.
    {
        string thisIsAvar; //this has been defined inside _privateMethod, and is ONLY available inside _privateMethod.
    }
    public void PublicMethod() //This is a public method. It can be called outside the class, on the class itself. Code running in here can still access the private variables inside the class.
    {
        _sPrivate = "I just changed the private var"; //This will work.
        thisIsAvar = "This is impossible, because thisIsAvar doesn't exist here"; //This will throw an error. Since thisIsAvar isn't defined inside this scope.
    }
}

C＃ - 从同一表单上的另一个私有void访问值

2 个答案: