如何用C#打开记事本文件放在窗体里

这是我琢磨的自己再理解理解
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace Example074_文本文件与RichTextBox
{
///

/// Form1 的摘要说明。
///

public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.RichTextBox richTextBox1;
private System.Windows.Forms.Button button1;
private System.Windows.Forms.Button button2;
private System.Windows.Forms.OpenFileDialog openFileDialog1;
private System.Windows.Forms.SaveFileDialog saveFileDialog1;
///

/// 必需的设计器变量。
///

private System.ComponentModel.Container components = null;

public Form1()
{
//
// Windows 窗体设计器支持所必需的
//
InitializeComponent();

//
// TODO: 在 InitializeComponent 调用后添加任何构造函数代码
//
}

///

/// 清理所有正在使用的资源。
///

protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}

#region Windows Form Designer generated code
///

/// 设计器支持所需的方法 - 不要使用代码编辑器修改
/// 此方法的内容。
///

private void InitializeComponent()
{
this.richTextBox1 = new System.Windows.Forms.RichTextBox();
this.button1 = new System.Windows.Forms.Button();
this.button2 = new System.Windows.Forms.Button();
this.openFileDialog1 = new System.Windows.Forms.OpenFileDialog();
this.saveFileDialog1 = new System.Windows.Forms.SaveFileDialog();
this.SuspendLayout();
//
// richTextBox1
//
this.richTextBox1.Location = new System.Drawing.Point(8, 8);
this.richTextBox1.Name = "richTextBox1";
this.richTextBox1.Size = new System.Drawing.Size(224, 192);
this.richTextBox1.TabIndex = 0;
this.richTextBox1.Text = "richTextBox1";
//
// button1
//
this.button1.Location = new System.Drawing.Point(8, 208);
this.button1.Name = "button1";
this.button1.Size = new System.Drawing.Size(75, 23);
this.button1.TabIndex = 1;
this.button1.Text = "Open";
this.button1.Click += new System.EventHandler(this.button1_Click);
//
// button2
//
this.button2.Location = new System.Drawing.Point(160, 208);
this.button2.Name = "button2";
this.button2.Size = new System.Drawing.Size(75, 23);
this.button2.TabIndex = 2;
this.button2.Text = "Save";
this.button2.Click += new System.EventHandler(this.button2_Click);
//
// saveFileDialog1
//
this.saveFileDialog1.FileName = "doc1";
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
this.ClientSize = new System.Drawing.Size(240, 237);
this.Controls.Add(this.button2);
this.Controls.Add(this.button1);
this.Controls.Add(this.richTextBox1);
this.Name = "Form1";
this.Text = "Form1";
this.Load += new System.EventHandler(this.Form1_Load);
this.ResumeLayout(false);

}
#endregion

///

/// 应用程序的主入口点。
///

[STAThread]
static void Main()
{
Application.Run(new Form1());
}

private void button1_Click(object sender, System.EventArgs e)
{
if(this.openFileDialog1.ShowDialog()==DialogResult.OK)
{
this.richTextBox1.LoadFile(this.openFileDialog1.FileName,RichTextBoxStreamType.PlainText);
}
}

private void button2_Click(object sender, System.EventArgs e)
{
if(this.saveFileDialog1.ShowDialog()==DialogResult.OK)
{
this.richTextBox1.SaveFile(this.saveFileDialog1.FileName,RichTextBoxStreamType.PlainText);
}
}

}
}

在c#中操作文件的方式要用到system.io这个命名空间下的类，比如file,Directory等。
打开记事本你可以直接这样：
string fileContent=System.IO.File.ReadAllText(文件路径","使用的编码方式");
当然也可以直接string fileContent=System.IO.File.ReadAllText(文件路径"）；
这样fileContent就是你文本的内容了
还有更深点的，你可以使用文件流的方式读取，如果不明白我们可以慢慢探讨，互相学习。