c# 读写、创建文件

Question

写了段用于创建文件的代码，大致功能是判断文件是否存在，如不存在就创建该文件，如果存在就对文件内容清空，代码如下，运行时出现问题：在没有该文件存在要创建时报文件进程被占用。请教大家问题在哪，代码如下：
              StreamWriter sw;
                if (!File.Exists(para.wpath + "\\data\\time.dat"))
                {
                    if (!Directory.Exists(para.wpath + "\\data"))
                    {
                        Directory.CreateDirectory(para.wpath + "\\data");
                        File.CreateText(para.wpath + "\\data\\time.dat");
                    }
                    else
                    {
                        File.CreateText(para.wpath + "\\data\\time.dat");                    }
                }
                else
                {
                    File.WriteAllText(para.wpath + "\\data\\time.dat", "");
                }
                 sw= new StreamWriter(para.wpath + "\\data\\time.dat");
                 sw.WriteLine("98547");
                 sw.Close();C#

Answer 1

把流关闭掉。
 if (!Directory.Exists("\\data"))
                {
                    Directory.CreateDirectory("\\data");
                    StreamWriter writer = File.CreateText("\\data\\time.dat");
                    writer.Close();
                }

Answer 2

 if (!Directory.Exists(para.wpath + "\\data"))
            {
                Directory.CreateDirectory("\\data");
            }
            if (!File.Exists(para.wpath + "\\data\\time.dat"))
            {
                File.WriteAllText(para.wpath + "\\data\\time.dat","", Encoding.GetEncoding("gb2312"));//直接这个就行了
            }

Answer 3

您好 按您说的成功了，后面这段代码只能写入第一行数据，以前用过不是这样的，能麻烦看看吗？
 private void button2_Click(object sender, EventArgs e)     //确定按钮，导出time
        {
            //===================================================获取数据点数
            for (int i = 1; i < 49; i++)
            {
                TextBox tb = this.groupBox1.Controls["textBox" + i.ToString()] as TextBox;
                if (tb.Text == "")
                {
                    tnum = (i - 1) / 2;
                    break;
                }            }
            //======================================================写time.dat文件
            StreamWriter sw;
            if (para.curnum == "1")
            {
                para.timenum = tnum;
                if (!File.Exists(para.wpath + "\\data\\time.dat"))
                {
                    if (!Directory.Exists(para.wpath + "\\data"))
                    {
                        Directory.CreateDirectory(para.wpath + "\\data");
                        sw = File.CreateText(para.wpath + "\\data\\time.dat");
                        sw.Close();
                    }
                    else
                    {
                        sw = File.CreateText(para.wpath + "\\data\\time.dat");
                        sw.Close();
                    }
                }
                else
                {
                    File.WriteAllText(para.wpath + "\\data\\time.dat","");
                }                sw = new StreamWriter(para.wpath + "\\data\\time.dat");                for (int i = 1; i == tnum; i++)
                {
                    TextBox tb = this.groupBox1.Controls["textBox" + (2 * i - 1).ToString()] as TextBox;
                    sw.WriteLine("S_time(" + i.ToString() + ") =" + (int.Parse(tb.Text) * 3600).ToString());
                }
                sw.Close();
            } 

Answer 4

for 语句使用问题...低级了