WPF操作CSV文件类型

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`public class CsvStreamReaderHepler { #region CSV文件读取 public static DataTable OpenCSV(string filePath)//从csv读取数据返回table { System.Text.Encoding encoding = GetType(filePath); //Encoding.ASCII;// DataTable dt = new DataTable(); System.IO.FileStream fs = new System.IO.FileStream(filePath, System.IO.FileMode.Open, System.IO.FileAccess.Read);

        System.IO.StreamReader sr = new System.IO.StreamReader(fs, encoding);

        //记录每次读取的一行记录
        string strLine = "";
        //记录每行记录中的各字段内容
        string[] aryLine = null;
        string[] tableHead = null;
        //标示列数
        int columnCount = 0;
        //标示是否是读取的第一行
        bool IsFirst = true;
        //逐行读取CSV中的数据
        int readCol = 0;
        while ((strLine = sr.ReadLine()) != null)
        {
            if (readCol > 0)
            {
                if (IsFirst == true)
                {
                    tableHead = strLine.Split(',');
                    IsFirst = false;
                    columnCount = tableHead.Length;
                    //创建列
                    for (int i = 0; i < columnCount; i++)
                    {
                        DataColumn dc = new DataColumn(tableHead[i]);
                        dt.Columns.Add(dc);
                    }
                }
                else
                {
                    aryLine = strLine.Split(',');
                    DataRow dr = dt.NewRow();
                    for (int j = 0; j < columnCount; j++)
                    {
                        dr[j] = aryLine[j];
                    }
                    dt.Rows.Add(dr);
                }
            }
            readCol++;
        }
        if (aryLine != null && aryLine.Length > 0)
        {
            dt.DefaultView.Sort = tableHead[0] + " " + "asc";
        }

        sr.Close();
        fs.Close();
        return dt;
    }
    /// 给定文件的路径，读取文件的二进制数据，判断文件的编码类型
    /// <param name="FILE_NAME">文件路径</param>
    /// <returns>文件的编码类型</returns>

    public static System.Text.Encoding GetType(string FILE_NAME)
    {
        System.IO.FileStream fs = new System.IO.FileStream(FILE_NAME, System.IO.FileMode.Open,
            System.IO.FileAccess.Read);
        System.Text.Encoding r = GetType(fs);
        fs.Close();
        return r;
    }

    /// 通过给定的文件流，判断文件的编码类型
    /// <param name="fs">文件流</param>
    /// <returns>文件的编码类型</returns>
    public static System.Text.Encoding GetType(System.IO.FileStream fs)
    {
        byte[] Unicode = new byte[] { 0xFF, 0xFE, 0x41 };
        byte[] UnicodeBIG = new byte[] { 0xFE, 0xFF, 0x00 };
        byte[] UTF8 = new byte[] { 0xEF, 0xBB, 0xBF }; //带BOM
        System.Text.Encoding reVal = System.Text.Encoding.Default;

        System.IO.BinaryReader r = new System.IO.BinaryReader(fs, System.Text.Encoding.Default);
        int i;
        int.TryParse(fs.Length.ToString(), out i);
        byte[] ss = r.ReadBytes(i);
        if (IsUTF8Bytes(ss) || (ss[0] == 0xEF && ss[1] == 0xBB && ss[2] == 0xBF))
        {
            reVal = System.Text.Encoding.UTF8;
        }
        else if (ss[0] == 0xFE && ss[1] == 0xFF && ss[2] == 0x00)
        {
            reVal = System.Text.Encoding.BigEndianUnicode;
        }
        else if (ss[0] == 0xFF && ss[1] == 0xFE && ss[2] == 0x41)
        {
            reVal = System.Text.Encoding.Unicode;
        }
        r.Close();
        return reVal;
    }

    /// 判断是否是不带 BOM 的 UTF8 格式
    /// <param name="data"></param>
    /// <returns></returns>
    private static bool IsUTF8Bytes(byte[] data)
    {
        int charByteCounter = 1;  //计算当前正分析的字符应还有的字节数
        byte curByte; //当前分析的字节.
        for (int i = 0; i < data.Length; i++)
        {
            curByte = data[i];
            if (charByteCounter == 1)
            {
                if (curByte >= 0x80)
                {
                    //判断当前
                    while (((curByte <<= 1) & 0x80) != 0)
                    {
                        charByteCounter++;
                    }
                    //标记位首位若为非0 则至少以2个1开始 如:110XXXXX...........1111110X　
                    if (charByteCounter == 1 || charByteCounter > 6)
                    {
                        return false;
                    }
                }
            }
            else
            {
                //若是UTF-8 此时第一位必须为1
                if ((curByte & 0xC0) != 0x80)
                {
                    return false;
                }
                charByteCounter--;
            }
        }
        if (charByteCounter > 1)
        {
            throw new Exception("非预期的byte格式");
        }
        return true;
    }
    #endregion
}

`