C#打开保存txt文件

using System.IO;

OpenFileDialog

Stream  mystream=null;
OpenFileDialog FileDialog1 = new OpenFileDialog();
FileDialog1.Filter = "txt files(*.txt)|*.txt|All Files(*.*)|*.*";
if(FileDialog1.ShowDialog()==DialogResult.OK)
{
try
{
if((mystream=FileDialog1.OpenFile())!=null)
{
st=new StreamReader(FileDialog1.FileName,Encoding.GetEncoding("gb2312"));
string str=st.ReadLine();
richTextBox1.Text = "";
while(str!=null)
{
richTextBox1.AppendText(str + "\n");
str=st.ReadLine();
}
richTextBox1.AppendText("\n");
}
}
catch(Exception ex)
{
MessageBox.Show("打开文件出错："+ex.Message);
}
textBox_FileName.Text = FileDialog1.FileName;
}

StreamReader

if (textBox_FileName.Text == "")
{
MessageBox.Show("请先打开文件！");
return;
}

st = new StreamReader(textBox_FileName.Text, Encoding.GetEncoding("gb2312"));
string str = st.ReadLine();
richTextBox1.Text = "";
while (str != null)
{
string[] temp;
if (str!="")
{
temp = str.Split(',');
if (temp.Length != 2)
{
MessageBox.Show("txt中经纬度格式有误，每行一组数据，以英文逗号隔开");
return;
}
if (Convert.ToDouble(temp[0]) > 90.0 || Convert.ToDouble(temp[1]) > 180.0)
{
MessageBox.Show("经纬度BL不在合理的范围内");
return;
}
richTextBox1.AppendText(str + "\n");
BL2XY(Convert.ToDouble(temp[0]), Convert.ToDouble(temp[1]));
richTextBox1.AppendText("\n");
}
str = st.ReadLine();
}
save_file("BL2XY");

SaveFileDialog
public void save_file(string zhengSuanOrfanSuan)
{
SaveFileDialog saveFileDialog1 = new SaveFileDialog();
saveFileDialog1.FileName = textBox_FileName.Text + "_" + zhengSuanOrfanSuan;
saveFileDialog1.Filter = "txt files(*.txt)|*.txt|All Files(*.*)|*.*";
saveFileDialog1.RestoreDirectory = true;
DialogResult dr = saveFileDialog1.ShowDialog();
if(dr==DialogResult.OK&&saveFileDialog1.FileName.Length>0)
{
richTextBox1.SaveFile(saveFileDialog1.FileName, RichTextBoxStreamType.PlainText);
MessageBox.Show("存储文件成功", "保存文件");
}
}

转：C#用openfiledialog文件和savefileDialog打开和保存文件