如何使用 C# 和 OleDbConnection 读取 .xlsx 和 .xls 文件？

Question

以前我使用ExcelPackage 从 .xlsx 文件中读取数据。那工作正常，但后来我意识到ExcelPackage 不适用于旧的 .xls 格式。所以我升级为使用OleDbConnection 而不是ExcelPackage，如下所示：

var 文件 = HttpContext.Current.Request.Files[0];
数据表 sheetData = new DataTable();
string connStr = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" +
    file.FileName + "; Jet OLEDB:Engine Type=5;Extended Properties=\"Excel 8.0;\"";

使用 (OleDbConnection conn = new OleDbConnection(connStr))
{
    conn.Open();
    DataTable dtSchema = conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, new object[] { null, null, null, "TABLE" });
    字符串 sheetName = dtSchema.Rows[0].Field("TABLE_NAME");
    OleDbDataAdapter sheetAdapter = new OleDbDataAdapter("select * from [" + sheetName + "]", conn);
    sheetAdapter.Fill(sheetData);
}

基本上只是试图阅读那里的第一个电子表格。但是我在异常中得到了这个错误：

Cannot update. Database or object is read-only.

我做错了什么？里面是否隐藏着某种更新操作？

Answer 1

下面是一个示例方法，它从给定的 excel 文件路径返回 DataSet。返回的DataSet 应该将工作簿中的每个 Excel 工作表作为DataTable 在DataSet 中。这似乎工作正常，希望它可以帮助。

private DataSet GetExcelDataSet(string path) {
  string sheetName;
  string ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + path +
                        "; Jet OLEDB:Engine Type = 5; Extended Properties =\"Excel 8.0;\"";
  DataSet ds = new DataSet();
  using (OleDbConnection con = new OleDbConnection(ConnectionString)) {
    using (OleDbCommand cmd = new OleDbCommand()) {
      using (OleDbDataAdapter oda = new OleDbDataAdapter()) {
        cmd.Connection = con;
        con.Open();
        DataTable dtExcelSchema = con.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
        for (int i = 0; i < dtExcelSchema.Rows.Count; i++) {
          sheetName = dtExcelSchema.Rows[i]["TABLE_NAME"].ToString();
          DataTable dt = new DataTable(sheetName);
          cmd.Connection = con;
          cmd.CommandText = "SELECT * FROM [" + sheetName + "]";
          oda.SelectCommand = cmd;
          oda.Fill(dt);
          dt.TableName = sheetName;
          ds.Tables.Add(dt);
        }
      }
    }
  }
  return ds;
}

Answer 2

试试这个：

OleDbConnection connection;
OleDbCommand command;
OleDbDataReader dr;

        string commandText = "SELECT * FROM [Sheet1$]";
        string oledbConnectString = "Provider=Microsoft.ACE.OLEDB.12.0;" +
        @"Data Source=" + filename + ";" +
        "Extended Properties=\"Excel 12.0;HDR=YES\";";
        connection = new OleDbConnection(oledbConnectString);
        command = new OleDbCommand(commandText, connection);

        try
        {
            connection.Open();
            dr = command.ExecuteReader();

            while (dr.Read())
            {
                count++;

                for (int i = 1; i < dr.VisibleFieldCount; i++)
                {
                   Console.Writeln(""+dr[i].ToString());
                }
            }

            connection.Close();
        }
        catch (Exception ex)
        {
            MessageBox.Show("" + ex.Message);
            connection.Close();
        }