C sharp应用下的CSV文件写入和读出

1. 建立DataTable 类型

DataTable my_accurdt;
my_accurdt = new DataTable(DateTime.Now.ToString("yMMddHHmm") + "_AccurData");

2. 创建DataTable的列和行

//列
my_accurdt.Columns.Add(new DataColumn("Oder", typeof(int)));
my_accurdt.Columns.Add(new DataColumn("TimeStamp", typeof(string)));

//行
DataRow my_rows = my_accurdt.NewRow();
my_rows["Oder"] = dataTableOrder;
my_rows["TimeStamp"] = DateTime.Now.ToString("yMMddHHmm");
my_accurdt.Rows.Add(my_rows);

3. 把DataTable显示在WinForm的dataGridView控件中

Accur_table_dataGridView.DataSource = my_accurdt;

4. 创建写入CSV文件方法

//write function
public void writeDataCSV(string file_path, DataTable my_dt)
{
    FileStream my_filestream;
    StreamWriter my_streamwriter;
    string my_data = null;
    if (!File.Exists(file_path))
    {
        my_filestream = new FileStream(file_path, FileMode.Create, FileAccess.Write);
        my_streamwriter = new StreamWriter(my_filestream, Encoding.UTF8);
        //write columns name
        for (int i = 0; i < my_dt.Columns.Count; i++)
        {
            my_data += my_dt.Columns[i].ColumnName.ToString();
            if (i < my_dt.Columns.Count - 1)
            {
                my_data += ",";
            }
        }
        my_streamwriter.WriteLine(my_data);
    }
    else
    {
        my_filestream = new FileStream(file_path, FileMode.Append, FileAccess.Write);
        my_streamwriter = new StreamWriter(my_filestream, Encoding.UTF8);
    }
    //write rows
    for (int i = 0; i < my_dt.Rows.Count; i++)
    {
        my_data = null;
        for (int j = 0; j < my_dt.Columns.Count; j++)
        {
            my_data += my_dt.Rows[i][j].ToString();
            if (j < my_dt.Columns.Count - 1)
            {
                my_data += ",";
            }
        }
        my_streamwriter.WriteLine(my_data);
    }
    my_streamwriter.Close();
    my_filestream.Close();
}

5. 创建读出CSV文件方法

//read function
public DataTable readDataCSV(string file_path)
{
    DataTable my_dt = new DataTable();
    FileStream my_filestream = new FileStream(file_path, FileMode.Open, FileAccess.Read);
    StreamReader my_streamreader = new StreamReader(my_filestream, Encoding.UTF8);
    string my_strLine = null;
    string[] my_arrayLine = null;
    bool isFirst = true;
    int my_dtColumns = 0;

    while ((my_strLine = my_streamreader.ReadLine()) != null)
    {
        my_strLine = my_strLine.Trim();
        my_arrayLine = my_strLine.Split(',');

        if (isFirst)
        {
            my_dtColumns = my_arrayLine.Length;
            for (int i = 0; i < my_dtColumns; i++)
            {
                my_dt.Columns.Add(my_arrayLine[i]);
            }
            isFirst = false;
        }
        else
        {
            DataRow my_datarow = my_dt.NewRow();
            for (int j = 0; j < my_dtColumns; j++)
            {
                if (my_arrayLine.Length > j)
                {
                    my_datarow[j] = my_arrayLine[j];
                }
            }
            my_dt.Rows.Add(my_datarow);
        }
    }
    my_streamreader.Close();
    my_filestream.Close();
    return my_dt;
}

6. 创建文件保存路径选择框

//file storage path
public string SelectFolderPath()
{
    string my_folderpath = string.Empty;
    FolderBrowserDialog my_folderbrowser = new FolderBrowserDialog();
    DialogResult my_result = my_folderbrowser.ShowDialog();
    if (my_result == DialogResult.OK)
    {
        my_folderpath = my_folderbrowser.SelectedPath;
        return my_folderpath;
    }
    else
    { return string.Empty; }
}