读取文本文件，更新字段C#和WPF

string filePath = "file.txt";
string fileContent = File.ReadAllText(filePath);

string updatedContent = fileContent.Replace("oldValue", "newValue");

<Window x:Class="TextFileUpdateExample.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Text File Update Example" Height="350" Width="500">
    <Grid>
        <TextBox x:Name="txtContent" TextWrapping="Wrap" AcceptsReturn="True" VerticalScrollBarVisibility="Auto"/>
        <Button Content="Update Field" Click="BtnUpdate_Click" HorizontalAlignment="Right" VerticalAlignment="Bottom" Margin="10"/>
    </Grid>
</Window>

using System.IO;
using System.Windows;

namespace TextFileUpdateExample
{
    public partial class MainWindow : Window
    {
        private string filePath = "file.txt";

        public MainWindow()
        {
            InitializeComponent();
            LoadFileContent();
        }

        private void LoadFileContent()
        {
            if (File.Exists(filePath))
            {
                string fileContent = File.ReadAllText(filePath);
                txtContent.Text = fileContent;
            }
        }

        private void BtnUpdate_Click(object sender, RoutedEventArgs e)
        {
            string updatedContent = txtContent.Text.Replace("oldValue", "newValue");
            File.WriteAllText(filePath, updatedContent);
            MessageBox.Show("Field updated successfully!");
        }
    }
}