导出Excel

同事找的方法,收录备用。

public string DataTableToExcel(DataTable dt, string excelPath)
    {
        if (dt == null)
        {
            throw new ArgumentException("DataTable is not Finded!");
        }

        int rows = dt.Rows.Count;
        int cols = dt.Columns.Count;
        StringBuilder sb;
        string connString;

        if (rows == 0)
        {
            throw new ArgumentException("No Data");
        }

        sb = new StringBuilder();
        connString = string.Format("Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0:G};Extended Properties=Excel 8.0", excelPath);

        #region 生成创建表的脚本
        sb.Append("CREATE TABLE 表");
        sb.Append(dt.TableName + "(");

        for (int i = 0; i < cols; i++)
        {
            if (i < cols - 1)
                sb.Append(string.Format("{0} varchar,", dt.Columns[i].ColumnName));
            else
                sb.Append(string.Format("{0} varchar)", dt.Columns[i].ColumnName));
        }

        using (OleDbConnection objConn = new OleDbConnection(connString))
        {
            OleDbCommand objCmd = new OleDbCommand();
            objCmd.Connection = objConn;

            objCmd.CommandText = sb.ToString();

            try
            {
                if (objConn.State == 0)
                {
                    objConn.Open();
                    objCmd.ExecuteNonQuery();
                }

            }
            catch (Exception e)
            {
                objConn.Close();
                throw;
            }
        #endregion
            #region 生成插入数据脚本
            //sb.Remove(0, sb.Length);
            sb = new StringBuilder();
            sb.Append("INSERT INTO 表");
            sb.Append(dt.TableName + " ( ");

            for (int i = 0; i < cols; i++)
            {
                if (i < cols - 1)
                    sb.Append(dt.Columns[i].ColumnName + ",");
                else
                    sb.Append(dt.Columns[i].ColumnName + ") values (");
            }

            for (int i = 0; i < cols; i++)
            {
                if (i < cols - 1)
                    sb.Append("@" + dt.Columns[i].ColumnName + ",");
                else
                    sb.Append("@" + dt.Columns[i].ColumnName + ")");
            }
            #endregion


            //建立插入动作的Command
            objCmd.CommandText = sb.ToString();
            OleDbParameterCollection param = objCmd.Parameters;

            for (int i = 0; i < cols; i++)
            {
                param.Add(new OleDbParameter("@" + dt.Columns[i].ColumnName, OleDbType.VarChar));
            }

            //遍历DataTable将数据插入新建的Excel文件中
            foreach (DataRow row in dt.Rows)
            {
                for (int i = 0; i < param.Count; i++)
                {
                    param[i].Value = row[i];
                }

                objCmd.ExecuteNonQuery();
            }

            return "数据已成功导入Excel";
        }//end using
    }