选择上点击它的TextBox的全部内容(Selecting all contents of Text

我有一个文本框。 在点击它，文本框的所有内容应选择。 ，这是什么解决办法吗？ 我曾尝试的代码是：

<TextBox Name="questionTitle_textBox" Text="Question title" PreviewMouseDown="questionTitle_textBox_PreviewMouseDown"/>

功能questionTitle_textBox_PreviewMouseDown被定义为

private void questionTitle_textBox_PreviewMouseDown(object sender, System.Windows.Input.MouseButtonEventArgs e)
{
        questionTitle_textBox.SelectAll();
}

Answer 1:

这工作

<TextBox Name="questionTitle_textBox" Text="Question title" GotFocus="questionTitle_textBox_GotFocus" PreviewMouseLeftButtonDown="questionTitle_textBox_PreviewMouseLeftButtonDown"/>

并在后面的代码

private void questionTitle_textBox_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
    TextBox tb = (sender as TextBox);
    if (tb != null)
    {
        if (!tb.IsFocused)
        {
            e.Handled = true;
            tb.Focus();
        }
    }
}

private void questionTitle_textBox_GotFocus(object sender, RoutedEventArgs e)
{
    TextBox tb = (sender as TextBox);
    if (tb != null)
    {
        tb.SelectAll();
    }
}

Answer 2:

你可以尝试将触发添加到您的文本框

<TextBox Name="questionTitle_textBox" Text="Question title" >
    <i:Interaction.Triggers>
        <i:EventTrigger EventName="GotFocus">
            <local:SelectAllAction />
        </i:EventTrigger>
    </i:Interaction.Triggers>
</TextBox>

添加SelectAllAction.cs到您的项目：

namespace YourNameSpace
{
    public class SelectAllAction : TriggerAction<TextBox>
    {
        protected override void Invoke(object parameter)
        {
            if(this.AssociatedObject != null)
            {
                this.AssociatedObject.SelectAll();
            }
        }
    }
}

您还需要两个namepsaces添加到您的XAML使用触发器。 我的项目名称是WpfApplication1，所以你可能会需要更改：

xmlns:local ="clr-namespace:YourNameSpace" 
xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"

文章来源: Selecting all contents of TextBox on clicking it