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在現實項目標開辟進程中，所觸及的EXCEL常常會比擬龐雜，而且列中還會帶有一些盤算公式，這就給讀取帶來了很年夜的艱苦，已經測驗考試過一些收費的第三方dll，比方Myxls，NPOI，IExcelDataReader都邑湧現一些成績，最初采取OLEDB情勢讀取，再x64操作體系上有點成績，不外采取小技能便可處理，可以參考鏈接地址：http://ellisweb.net/2010/01/connecting-to-excel-and-access-files-using-net-on-a-64-bit-server/
封裝代碼以下：
namespace DBUtilHelpV2
{
public class OLEDBExcelToolV2
{
static readonly string xls = ".xls";
static readonly string xlsx = ".xlsx";
string _ExcelExtension = string.Empty;//後綴
string _ExcelPath = string.Empty;//途徑
string _ExcelConnectString = string.Empty;//鏈接字符串
static bool _X64Version = false;//能否強迫應用x64鏈接字符串，即xlsx情勢
public OLEDBExcelToolV2(string excelPath, bool x64Version)
{
if (string.IsNullOrEmpty(excelPath))
throw new ArgumentNullException("excelPath");
if (!File.Exists(excelPath))
throw new ArgumentException("excelPath");
string _excelExtension = Path.GetExtension(excelPath);
_ExcelExtension = _excelExtension.ToLower();
_ExcelPath = excelPath;
_X64Version = x64Version;
_ExcelConnectString = BuilderConnectionString();
}
/// <summary>
/// 創立鏈接字符串
/// </summary>
/// <returns></returns>
private string BuilderConnectionString()
{
Dictionary<string, string> _connectionParameter = new Dictionary<string, string>();
if (!_ExcelExtension.Equals(xlsx) && !_ExcelExtension.Equals(xls))
{
throw new ArgumentException("excelPath");
}
if (!_X64Version)
{
if (_ExcelExtension.Equals(xlsx))
{
// XLSX - Excel 2007, 2010, 2012, 2013
_connectionParameter["Provider"] = "Microsoft.ACE.OLEDB.12.0;";
_connectionParameter["Extended Properties"] = "'Excel 12.0 XML;IMEX=1'";
}
else if (_ExcelExtension.Equals(xls))
{
// XLS - Excel 2003 and Older
_connectionParameter["Provider"] = "Microsoft.Jet.OLEDB.4.0";
_connectionParameter["Extended Properties"] = "'Excel 8.0;IMEX=1'";
}
}
else
{
_connectionParameter["Provider"] = "Microsoft.ACE.OLEDB.12.0;";
_connectionParameter["Extended Properties"] = "'Excel 12.0 XML;IMEX=1'";
}
_connectionParameter["Data Source"] = _ExcelPath;
StringBuilder _connectionString = new StringBuilder();
foreach (KeyValuePair<string, string> parameter in _connectionParameter)
{
_connectionString.Append(parameter.Key);
_connectionString.Append('=');
_connectionString.Append(parameter.Value);
_connectionString.Append(';');
}
return _connectionString.ToString();
}
/// <summary>
/// Excel操作
/// DELETE不支撐
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public int ExecuteNonQuery(string sql)
{
int _affectedRows = -1;
using (OleDbConnection sqlcon = new OleDbConnection(_ExcelConnectString))
{
try
{
sqlcon.Open();
using (OleDbCommand sqlcmd = new OleDbCommand(sql, sqlcon))
{
_affectedRows = sqlcmd.ExecuteNonQuery();
}
}
catch (Exception)
{
return -1;
}
}
return _affectedRows;
}
/// <summary>
/// Excel操作
///獲得EXCEL內sheet聚集
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public string[] GetExcelSheetNames()
{
DataTable _schemaTable = null;
using (OleDbConnection sqlcon = new OleDbConnection(_ExcelConnectString))
{
try
{
sqlcon.Open();
_schemaTable = sqlcon.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
String[] _excelSheets = new String[_schemaTable.Rows.Count];
int i = 0;
foreach (DataRow row in _schemaTable.Rows)
{
_excelSheets[i] = row["TABLE_NAME"].ToString().Trim();
i++;
}
return _excelSheets;
}
catch (Exception)
{
return null;
}
finally
{
if (_schemaTable != null)
{
_schemaTable.Dispose();
}
}
}
}
/// <summary>
/// 讀取sheet
/// eg:select * from [Sheet1$]
/// </summary>
/// <param name="sql"></param>
/// <returns></returns>
public DataTable ExecuteDataTable(string sql)
{
using (OleDbConnection sqlcon = new OleDbConnection(_ExcelConnectString))
{
try
{
using (OleDbCommand sqlcmd = new OleDbCommand(sql, sqlcon))
{
using (OleDbDataAdapter sqldap = new OleDbDataAdapter(sqlcmd))
{
DataTable _dtResult = new DataTable();
sqldap.Fill(_dtResult);
return _dtResult;
}
}
}
catch (Exception)
{
return null;
}
}
}
/// <summary>
/// 獲得excel一切sheet數據
/// </summary>
/// <returns>DataSet</returns>
public DataSet ExecuteDataSet()
{
DataSet _excelDb = null;
using (OleDbConnection sqlcon = new OleDbConnection(_ExcelConnectString))
{
try
{
sqlcon.Open();
DataTable _schemaTable = sqlcon.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
if (_schemaTable != null)
{
int i = 0;
_excelDb = new DataSet();
foreach (DataRow row in _schemaTable.Rows)
{
string _sheetName = row["TABLE_NAME"].ToString().Trim();
string _sql = string.Format("select * from [{0}]", _sheetName);
using (OleDbCommand sqlcmd = new OleDbCommand(_sql, sqlcon))
{
using (OleDbDataAdapter sqldap = new OleDbDataAdapter(sqlcmd))
{
DataTable _dtResult = new DataTable();
_dtResult.TableName = _sheetName;
sqldap.Fill(_dtResult);
_excelDb.Tables.Add(_dtResult);
}
}
i++;
}
}
}
catch (Exception)
{
return null;
}
}
return _excelDb;
}
}
}
代碼應用辦法以下：
/// <summary>
/// 歸並EXCEL數據
/// </summary>
/// <param name="_excelPath">excel途徑</param>
private void HandleMergeExcel(string _excelPath)
{
if (!string.IsNullOrEmpty(_excelPath))
{
OLEDBExcelToolV2 _excelHelper = new OLEDBExcelToolV2(_excelPath, true);
DataSet _excelSource = _excelHelper.ExecuteDataSet();
HandleExcelSource(_excelSource);
}
}
若在x64操作體系，將第二個參數設置true，而且依照AccessDatabaseEngine_X64.exe便可正常讀取
代碼運轉後果以下圖所示：
