TextBox上的MinLines和MaxLines无法正常工作

Question

任何人都可以解释为什么下面的TextBox最初没有显示为3行高？它显示1行高,然后在我开始键入文本时调整为3.

编辑:这里有一些表格

<Window x:Class="MyNamespace.Views.DetailsView"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:MV="clr-namespace:MyNamespace.Views"
    xmlns:prop="clr-namespace:MyNamespace.Properties"
    xmlns:toolkit="http://schemas.microsoft.com/wpf/2008/toolkit"
    MV:DialogCloser.DialogResult="{Binding Path=DialogResult, Mode=TwoWay}"
    Background="{StaticResource {x:Static SystemColors.ControlBrushKey}}" 
    Title="{Binding Source={x:Static prop:Resources.MyView_Caption}}"
    SizeToContent="WidthAndHeight" 
    WindowStartupLocation="CenterScreen" 
    WindowStyle="SingleBorderWindow" 
    MinHeight="100" 
    MinWidth="250">
<StackPanel Name="AllItems" Orientation="Horizontal">
    <StackPanel Width="450" Margin="5">
        <StackPanel Margin="5,0,5,0" VerticalAlignment="Center">
            <DockPanel Margin="5" >
                <Label Content="Prompt"/>
                <TextBox MaxLines="3"
                     MinLines="3" 
                     VerticalScrollBarVisibility="Auto"
                     TextWrapping="Wrap" />
            </DockPanel>
        </StackPanel>
    </StackPanel>
</StackPanel>
...
</Window>

Answer 1

是的，我也遇到过这个问题。TextBox 最初在启动时不会正确调整大小，您可以通过将 Text 属性与启动文本绑定（例如空白空格值“”）来解决此问题。

XAML：

<StackPanel Margin="5,0,5,0" VerticalAlignment="Center">
 <DockPanel Margin="5" >
 <Label Content="Prompt"/>
 <TextBox MaxLines="3"
         MinLines="3" x:Name="text"
         VerticalScrollBarVisibility="Auto"
         Text="{Binding StartUpText}"
         AcceptsReturn="True"
         TextWrapping="Wrap" TextChanged="text_TextChanged" Loaded="text_Loaded"  />
 </DockPanel>
</StackPanel>

C＃：

public MainWindow()
    {
        InitializeComponent();
        this.DataContext=this;
         StartUpText = " ";
    }

private string startUpText;
public string StartUpText
{
  get { return startUpText; }
  set
  {
    if (value != startUpText)
    {
        startUpText = value;
    }
  }
}