如何在文本框、Powershell窗体中为搜索的字符串着色

正在尝试编写用于搜索字符串的简单Powershell表单。两个文本框，一个用于输出，另一个用于搜索

目标：编写要查找的字符串>按

enter

>搜索的字符串将在输出文本中着色（如果找到）

例如：

OutputBox-

例如文本

搜索框-

ex

---

在搜索操作-

t/red>/ex//ex/之后，我对选择颜色（
$outputBox.SelectionColor='red'
）进行了一些修改，并为单词ex的多次出现添加了颜色逻辑

代码修改：

$SearchInput.Add_KeyDown({if ($_.KeyCode -eq "Enter")
{
$counter = 0
$pos = $outputBox.Text.IndexOf($SearchInput.text,$counter)
 while($pos -ne -1) {
 $counter = $pos + $SearchInput.text.Length
$outputBox.SelectionStart = $pos
$outputBox.SelectionLength = $SearchInput.text.Length
$outputBox.SelectionColor = 'red'
$pos = $outputBox.Text.IndexOf($SearchInput.text,$counter)
}
}

脚本的独立工作版本：

add-type -assembly System.Windows.Forms
$form=New-Object System.Windows.Forms.Form
$form.StartPosition='CenterScreen'
$form.Size = New-Object System.Drawing.Size(1000,1000) 
$outputBox = New-Object System.Windows.Forms.RichTextBox
$outputBox.Location = New-Object System.Drawing.Size(0,250) 
$outputBox.Size = New-Object System.Drawing.Size(780,405) 
$outputBox.MultiLine = $True 
$outputBox.ForeColor = "White"
$outputBox.BackColor = "Black"
$outputBox.ScrollBars = "Vertical" 
$outputBox.Text = "text for example"
$outputBox.ReadOnly=$True
$Form.Controls.Add($outputBox) 
$SearchInput = New-Object System.Windows.Forms.TextBox 
$SearchInput.Dock = "Bottom"
$Form.Controls.Add($SearchInput) 

$SearchInput.Add_KeyDown({if ($_.KeyCode -eq "Enter")
{
$counter = 0
$pos = $outputBox.Text.IndexOf($SearchInput.text,$counter)
 while($pos -ne -1) {

 $counter = $pos + $SearchInput.text.Length
$outputBox.SelectionStart = $pos
$outputBox.SelectionLength = $SearchInput.text.Length
$outputBox.SelectionColor = 'red'
$pos = $outputBox.Text.IndexOf($SearchInput.text,$counter)
}
}
})

$form.ShowDialog()

PS：重复选择部分可以优化
工作，谢谢。搜索框为空时有一个无休止的循环，但修复起来很简单。你能解释一下最后一行吗？你为什么又这样做
$pos=$outputBox.Text.IndexOf（$SearchInput.Text，$counter）
@igor IndexOf函数第二个参数用于开始搜索的索引位置，IndexOf仅查找第一个匹配项，循环使用计数器更新起始位置。
$SearchInput.Add_KeyDown({if ($_.KeyCode -eq "Enter")
{
$counter = 0
$pos = $outputBox.Text.IndexOf($SearchInput.text,$counter)
 while($pos -ne -1) {
 $counter = $pos + $SearchInput.text.Length
$outputBox.SelectionStart = $pos
$outputBox.SelectionLength = $SearchInput.text.Length
$outputBox.SelectionColor = 'red'
$pos = $outputBox.Text.IndexOf($SearchInput.text,$counter)
}
}

add-type -assembly System.Windows.Forms
$form=New-Object System.Windows.Forms.Form
$form.StartPosition='CenterScreen'
$form.Size = New-Object System.Drawing.Size(1000,1000) 
$outputBox = New-Object System.Windows.Forms.RichTextBox
$outputBox.Location = New-Object System.Drawing.Size(0,250) 
$outputBox.Size = New-Object System.Drawing.Size(780,405) 
$outputBox.MultiLine = $True 
$outputBox.ForeColor = "White"
$outputBox.BackColor = "Black"
$outputBox.ScrollBars = "Vertical" 
$outputBox.Text = "text for example"
$outputBox.ReadOnly=$True
$Form.Controls.Add($outputBox) 
$SearchInput = New-Object System.Windows.Forms.TextBox 
$SearchInput.Dock = "Bottom"
$Form.Controls.Add($SearchInput) 

$SearchInput.Add_KeyDown({if ($_.KeyCode -eq "Enter")
{
$counter = 0
$pos = $outputBox.Text.IndexOf($SearchInput.text,$counter)
 while($pos -ne -1) {

 $counter = $pos + $SearchInput.text.Length
$outputBox.SelectionStart = $pos
$outputBox.SelectionLength = $SearchInput.text.Length
$outputBox.SelectionColor = 'red'
$pos = $outputBox.Text.IndexOf($SearchInput.text,$counter)
}
}
})

$form.ShowDialog()