excel、csv、txt文件数据读取

　　　　 /// <summary>
/// 读取Excel表每一行第一列的字符串集合
/// </summary>
/// <param name="filePath">文件路径</param>
/// <returns></returns>
private string[] ExcelReader(string filePath)
{
List<string> result = new List<string>();
string connStr = "Provider=Microsoft.Ace.OleDb.12.0;data source=" + filePath + ";Extended Properties='Excel 12.0; HDR=NO; IMEX=1'";
OleDbConnection Conn = new OleDbConnection(connStr);
Conn.Open();
DataTable dtTabeName = new DataTable();
dtTabeName = Conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
if (dtTabeName == null)
{
return null;
}
string SheetName = dtTabeName.Rows[0]["TABLE_NAME"].ToString();
DataSet ds = new DataSet();
OleDbDataAdapter odda = null;
odda = new OleDbDataAdapter(string.Format("SELECT * FROM [{0}]", SheetName), Conn);
odda.Fill(ds, SheetName);
Conn.Close();
DataTable dt = ds.Tables[0];
for (int i = 0; i < dt.Rows.Count; i++)
{
if (dt.Rows[i][0].ToString().Trim().Length > 0)
{
result.Add(dt.Rows[i][0].ToString());
}
}
return result.ToArray();
}

/// <summary>
/// 读取Csv\Txt文件中每一行第一列的字符串集合
/// </summary>
/// <param name="filePath">文件路径</param>
/// <param name="encoding">编码</param>
/// <returns></returns>
private string[] CsvTxtReader(string filePath, string encoding = "gb2312")
{
StringBuilder sb = new StringBuilder();
using (StreamReader sr = new StreamReader(filePath, Encoding.GetEncoding(encoding)))
{
sb.Append(sr.ReadToEnd());
}
string _text = sb.ToString();
string[] separator = { "\r\n", "\n\r", "\n" };
string[] _textArray = _text.Split(separator, StringSplitOptions.RemoveEmptyEntries);
return _textArray;
}