Question

目标是在按System.Windows.Forms.Label后更改System.Windows.Forms.Button的文本。我有以下OOP代码。哪个（almost）有效：

Add-Type -AssemblyName System.Windows.Forms
Add-Type -AssemblyName System.Drawing

class MyForm : System.Windows.Forms.Form {
    MyForm($mystuff) {
        #Do-Stuff
        $this.Add_Load( $this.MyForm_Load )
    }

    $MyForm_Load = {
        $mlabel = [System.Windows.Forms.Label]::new()
        $mlabel.Name = "status"
        $mlabel.Text = "enabled"

        $mbutton = [System.Windows.Forms.Button]::new() 
        $mbutton.Text = "toggle state"

        $mbutton.Location = [System.Drawing.Point]::new(100,100)
        $mbutton.Add_Click( $this.mbutton_click )

        $this.Controls.Add($mlabel)
        $this.Controls.Add($mbutton)
    }

    $mbutton_click = {
        if ($this.Parent.Controls["status"].Text -eq "enabled"){
            $this.Parent.Controls["status"].Text = "disabled"
        }
        else{
            $this.Parent.Controls["status"].Text = "enabled"
        }
    }
}

$foo = [MyForm]::new("test")
$foo.ShowDialog()

现在我正在尝试将其重写为无法正常工作的程序样式：

Add-Type -AssemblyName System.Windows.Forms    
Add-Type -AssemblyName System.Drawing


$global:mbutton = [System.Windows.Forms.Button]::new()
    $mbutton.Text = "toggle state"   
    $mbutton.Location = [System.Drawing.Point]::new(100,100)
    # $mbutton.Add_Click( {Button_Click} ) # pressing button shows errors on console


$global:mlabel = [System.Windows.Forms.Label]::new()
        $mlabel.Name = "status"
        $mlabel.Text = "enabled"

$global:Form = New-Object System.Windows.Forms.Form
    $Form.Controls.Add($mlabel)
    $Form.Controls.Add($mbutton)
    $Form.ShowDialog() | Out-Null

    $mbutton.Add_Click( {Button_Click} ) # pressing button does nothing


Function Button_Click() {
    if ($Form.Parent.Controls["status"].Text -eq "enabled"){
        $Form.Parent.Controls["status"].Text = "disabled"
    }
    else{
        $Form.Parent.Controls["status"].Text = "enabled"
    }
}

我做错了什么？我该如何调试此类问题？

Answer 1

除非您绝对需要全局定义，否则最好不要使用全局定义。但是在这种情况下，如果您稍微改变事物的顺序，它将起作用：

Add-Type -AssemblyName System.Windows.Forms    
Add-Type -AssemblyName System.Drawing

Function Button_Click() {
    if ($mlabel.Text -eq "enabled"){
        $mlabel.Text = "disabled"
    }
    else{
        $mlabel.Text = "enabled"
    }
}

$global:mbutton = [System.Windows.Forms.Button]::new()
    $mbutton.Text = "toggle state"   
    $mbutton.Location = [System.Drawing.Point]::new(100,100)
    # $mbutton.Add_Click( {Button_Click} ) # pressing button shows errors on console


$global:mlabel = [System.Windows.Forms.Label]::new()
        $mlabel.Name = "status"
        $mlabel.Text = "enabled"

$global:Form = New-Object System.Windows.Forms.Form
    $Form.Controls.Add($mlabel)
    $Form.Controls.Add($mbutton)

    $mbutton.Add_Click( {Button_Click} ) # pressing button does nothing

    $Form.ShowDialog() | Out-Null

通常，将表单显示为最后一个操作是一种好习惯，因为您需要定义它所使用的所有内容，但是在任何情况下，都需要在显示表单之前定义一个click事件...

按下按钮后，winforms无动作

1 个答案: