如何将TextBlock绑定到通过绑定给出关键字的字典条目？

<Window x:Class="DictionaryBindingExample.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Dictionary Binding Example" Height="450" Width="800">
    <Grid>
        <TextBlock Text="{Binding Source={x:Static local:DictionaryHelper.MyDictionary}, Path=[MyKey]}" />
    </Grid>
</Window>

using System.Collections.Generic;

namespace DictionaryBindingExample
{
    public static class DictionaryHelper
    {
        public static Dictionary<string, string> MyDictionary { get; } = new Dictionary<string, string>()
        {
            { "MyKey", "This is the value for MyKey" },
            // 添加其他关键字和对应的条目
        };
    }
}