C# Excel to DataTable

 public static DataTable ToDataTable(string filePath)
        {
            string connStr = "";
            string tblName = "tb";
            string fileType = System.IO.Path.GetExtension(filePath);
            if (string.IsNullOrEmpty(fileType)) return null;

 

            if (fileType == ".xls")
                connStr = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + filePath + ";" + ";Extended Properties=\"Excel 8.0;HDR=YES;IMEX=1\"";
            else
                connStr = "Provider=Microsoft.ACE.OLEDB.12.0;" + "Data Source=" + filePath + ";" + ";Extended Properties=\"Excel 12.0;HDR=YES;IMEX=1\"";
            string sql_F = "Select * FROM [{0}]";

 

            OleDbConnection conn = null;
            OleDbDataAdapter da = null;
            DataTable dtSheetName = null;
            DataTable dt = new DataTable();

 

            DataSet ds = new DataSet();
            try
            {
                // 初始化连接，并打开 
                conn = new OleDbConnection(connStr);
                conn.Open();

 

                // 获取数据源的表定义元数据                        
                string SheetName = "";
                dtSheetName = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "TABLE" });

 

                // 初始化适配器 
                da = new OleDbDataAdapter();
                for (int i = 0; i < dtSheetName.Rows.Count; i++)
                {
                    SheetName = (string)dtSheetName.Rows[i]["TABLE_NAME"];

 

                    if (SheetName.Contains("$") && !SheetName.Replace("'", "").EndsWith("$"))
                    {
                        continue;
                    }

                    da.SelectCommand = new OleDbCommand(String.Format(sql_F, SheetName), conn);
                   // DataSet dsItem = new DataSet();
                    //DataTable dt = da.Fill();
                   
                    dt.TableName = "xlsTable";
                    da.Fill(dt);
                   // da.Fill(dsItem, tblName);
                    //ds.Tables.Add(dt.Copy());
                    //ds.Tables.Add(dsItem.Tables[0].Copy());
                  
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.ToString());
            }
            finally
            {
                // 关闭连接 
                if (conn.State == ConnectionState.Open)
                {
                    conn.Close();
                    da.Dispose();
                    conn.Dispose();
                }
            }
            return dt;
        } 

 

 

OpenFileDialog ofd = new OpenFileDialog();
            ofd.DefaultExt = "xls";
            ofd.Filter = "Excel|*.xls;*.xlsx";
   ofd.AddExtension = true;
            //string strPath;
            if (ofd.ShowDialog() == DialogResult.OK)
            {
                string text = ofd.FileName.ToString();
               // string exl=text.Substring(text.LastIndexOf('\\')+1) ;
                //string[] er = exl.Split('.');
               // ex = ex.Substring(0,text.LastIndexOf('.'));
               // MessageBox.Show(text);
              //  string[] excelName = GetExcelSheetNames(text);
               
               
               // MessageBox.Show(excelName.Length.ToString());
                if (string.Compare(Path.GetExtension(text), ".xls", true) != 0 && string.Compare(Path.GetExtension(text), ".xlsx", true) != 0)
                {
                    MessageBox.Show("Load File Name Error !!");
                }
                else
                {
                    try
                    {
                        /*
                        string strCon = string.Format("Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};Extended Properties='Excel 12.0;HDR=Yes;IMEX=1;'", text);
                        OleDbConnection Con = new OleDbConnection(strCon);//建立连接
                        string strSql = "select * from ["+excelName[0]+"$]";//表名的写法也应注意不同，对应的excel表为sheet1，在这里要在其后加美元符号$，并用中括号
                        OleDbCommand Cmd = new OleDbCommand(strSql, Con);//建立要执行的命令
                        OleDbDataAdapter da = new OleDbDataAdapter(Cmd);//建立数据适配器  */
                        // DataSet ds = new DataSet();//新建数据集
                       // DataSet ds = ToDataTable(text);
                        DataTable dt = ToDataTable(text);
                        //da.Fill(ds, "dataExcel");//把数据适配器中的数据读到数据集中的一个表中（此处表名为shyman，可以任取表名）
                        //指定datagridview1的数据源为数据集ds的第一张表（也就是shyman表），也可以写ds.Table["shyman"]
                        dgData.DataSource = dt;
                    }
                    catch (Exception ex)
                    {
                        MessageBox.Show(ex.Message);//捕捉异常
                    }
                    finally
                    {
                       
                    }
                }
            }