如何从C＃中的其他类访问MainWindow类工具

Question

I need to access textbox and label controls for other c# classes(not only MainWindow class) in wpf. I used x:FieldModifier="public" but still negative. Is it possible to populate MainWindow class Tools for other classes? Here is my simplified example code:

<Window x:Class="MyAbsClass.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:local="clr-namespace:MyAbsClass"
    mc:Ignorable="d"
    Title="MainWindow" Height="350" Width="525">
<Grid>
    <TextBox x:FieldModifier="public" x:Name="txt1"/>
    <TextBox x:FieldModifier="public" x:Name="txt2"/>
    <Button x:FieldModifier="public" x:Name="btn1" Content="Button" Click="btn1_Click"/>
</Grid>

namespace MyAbsClass
{   
class manipulate
{
    public void add()
    {
       int a=int32.Parse(txt1.Text);
       int b=int32.Parse(txt2.Text);
    }
}   

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();            
    }

    private void btn1_Click(object sender, RoutedEventArgs e)
    {
    MessageBox.Show("Added value= "+(a+b));
    }
}
}

Answer 1

You should always be passing this information to the class, this is separation of concerns and ensures when the view changes you don't have to update your other classes. It also means other classes can be reused.

You're also coming at this problem from the wrong way for WPF - you don't want to get the value from the TextBox, you want the TextBoxto set the value. You should use a binding for this.

Here is a working sample for you, I appreciate it doesn't directly answer your question but I hope it helps you in the right direction.

View:

<Window x:Class="WPFDynamicControls.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WPFDynamicControls"
        mc:Ignorable="d"
        Title="MainWindow" Height="350" Width="525" >
    <StackPanel>
        <TextBox Text="{Binding BoxA}"/>
        <TextBox Text="{Binding BoxB}"/>
        <Button Content="Add" Click="btn1_Click"/>
    </StackPanel>
</Window>

Code behind:

public partial class MainWindow : Window
{
    public MainWindow()
    {
        this.DataContext = this;
        InitializeComponent();
    }

    public int BoxA { get; set; }

    public int BoxB { get; set; }

    private void btn1_Click(object sender, RoutedEventArgs e)
    {
        MessageBox.Show("Added value= " + Manipulate.Add(this.BoxA, this.BoxB));
    }
}

public static class Manipulate
{
    public static int Add(int a, int b)
    {
        return a + b;
    }
}

Answer 2

var mainWindow = new MainWindow();
int a = int32.Parse(mainWindow.txt1.Text);
int b = int32.Parse(mainWindow.txt2.Text);

Answer 3

This method should give you access to anything in any window by passing the reference to a static property:

public partial class MainWindow : Window
{
    public static TextBox txt1Mirror;
    public static TextBox txt2Mirror;

    public MainWindow()
    {
        InitializeComponent();
        txt1Mirror = txt1;
        txt1Mirror = txt2;
    }

    private void btn1_Click(object sender, RoutedEventArgs e)
    {
        Manipulate.Add();
    }
}

public static class Manipulate
{
    public static void Add()
    {
       int a = int32.Parse(MainWindow.txt1Mirror.Text);
       int b = int32.Parse(MainWindow.txt2Mirror.Text);

       MessageBox.Show("Added value= " + (a + b));
    }
}

A Better More Clean Solution

You could simply use Binding with an Interface then pass the entire window:

<StackPanel>
    <TextBox Text="{Binding X}"/>
    <TextBox Text="{Binding Y}"/>
    <Button Content="Add" Click="Btn_Add"/>
</StackPanel>

Implement the Interface:

interface IManipulate
{
   int X { get; set; }
   int Y { get; set; }
}

Setup your window:

public partial class MainWindow : Window, IManipulate
{
    public int X { get; set; }
    public int Y { get; set; }

    public MainWindow()
    {
        InitializeComponent();
    }

    private void btn_Add(object sender, RoutedEventArgs e)
    {
        Manipulate.Add(this);
    }
}

public static class Manipulate
{
    public static void Add(IManipulate e)
    {
       MessageBox.Show("Added value= " + (e.X + e.Y).toString());
    }
}