C# 讀寫文件window form操作代碼

///////////創建文件和讀取文件的值

region 判斷文件是否存在，不存在則創建，否則讀取值顯示到窗體
public FormMain()
{
    InitializeComponent();

//ReadFile(Application.StartupPath + "AlarmSet.txt");

//也是判斷文件是否存在
//System.IO.DirectoryInfo info = new System.IO.DirectoryInfo(Application.StartupPath + "AlarmSet.txt");
//MessageBox.Show(info.Exists.ToString());

//MessageBox.Show(Application.StartupPath + "AlarmSet.txt");

//判斷文件是否存在
if (!File.Exists(Application.StartupPath + "AlarmSet.txt"))
{
    //File.Create(Application.StartupPath + "AlarmSet.txt");//創建該文件

    FileStream fs1 = new FileStream(Application.StartupPath + "AlarmSet.txt", FileMode.Create, FileAccess.Write);//創建寫入文件
    StreamWriter sw = new StreamWriter(fs1);
    sw.WriteLine("[runtype]");//開始寫入值
    sw.WriteLine("type=1");

    sw.WriteLine("rn");

    sw.WriteLine("--報警設置 PPWS 號牌匹配位數 PPWZ 匹配位置 0前匹配 1后匹配");
    sw.WriteLine("[Alarm]");
    sw.WriteLine("PPWZ=0");
    sw.WriteLine("PPWS=8");

    sw.WriteLine("rn");

    sw.WriteLine("[Server]");
    sw.WriteLine("ListenPort=2005");

    sw.WriteLine("rn");

    sw.WriteLine("[Form]");
    sw.WriteLine("PPWZ=0");

    sw.Close();
    fs1.Close();

}

//讀取文件值并顯示到窗體
FileStream fs = new FileStream(Application.StartupPath + "AlarmSet.txt", FileMode.Open, FileAccess.ReadWrite);
StreamReader sr = new StreamReader(fs);
string line = sr.ReadLine();
int curLine = 0;
while (line != null)
{
    if (++curLine == 7 && line.Equals("PPWZ=0"))//文件第7行并且值為PPWZ=0的時候設置單選鈕選中前匹配
    {
        radioButton1.Checked = true;
        radioButton2.Checked = false;
        //MessageBox.Show("前");
    }
    else if (curLine == 8 && line.Equals("PPWZ=1"))//文件第8行并且值為PPWZ=1的時候設置單選鈕選中后匹配
    {
        radioButton2.Checked = true;
        radioButton1.Checked = false;
        //MessageBox.Show("后");
    }

    if (curLine == 8)//文件第8行
    {
        textBox1.Text = line.Substring(line.LastIndexOf("=") + 1);//截取=號后邊的值
    }

    //MessageBox.Show("第" + (++curLine).ToString() + "行:   " + line);
    //Console.WriteLine("第" + (++curLine).ToString() + "行:   " + line);
    line = sr.ReadLine();
}
sr.Close();
fs.Close();

}
endregion
///修改文件的值
region 保存設置 按鈕 按下
private void button6_Click(object sender, EventArgs e)
{
    if(radioButton1.Checked == true )
    {
        EditFile(7, "PPWZ=0", Application.StartupPath + "AlarmSet.txt");
        EditFile(8, "PPWS=" + textBox1.Text, Application.StartupPath + "AlarmSet.txt");
    }

if (radioButton2.Checked == true)
{
    EditFile(7, "PPWZ=1", Application.StartupPath + "AlarmSet.txt");
    EditFile(8, "PPWS=" + textBox1.Text, Application.StartupPath + "AlarmSet.txt");
}

}
endregion
region 設置匹配
public static void EditFile(int curLine, string newLineValue, string patch)
{
    FileStream fs = new FileStream(patch, FileMode.Open, FileAccess.Read);
    StreamReader sr = new StreamReader(fs, Encoding.GetEncoding("utf-8"));//解決寫入文件亂碼
    string line = sr.ReadLine();
    StringBuilder sb = new StringBuilder();
    for (int i = 1; line != null; i++)
    {
        sb.Append(line + "rn");
        if (i != curLine - 1)
            line = sr.ReadLine();
        else
        {
            sr.ReadLine();
            line = newLineValue;
        }
    }
    sr.Close();
    fs.Close();
    FileStream fs1 = new FileStream(patch, FileMode.Open, FileAccess.Write);
    StreamWriter sw = new StreamWriter(fs1);
    sw.Write(sb.ToString());
    sw.Close();
    fs.Close();
}
endregion</pre>