Question

在下面执行此SQL Select Statement时，有两种情况需要检查..

retrieveQuery = "SELECT itemName, itemCategory, itemSubCategory, itemPrice, orders, (orders * itemPrice) as TotalPrice FROM Menu WHERE itemCategory = @selectedCat AND itemSubCategory LIKE '%@selectedSubCat%'";

参数化查询中的2个字段为selectedCat和selectedSubCat。

第一种情况是当用户仅选择Food时，您可以看到所选的DropdownList值为ALL，这意味着查询语句的Where Clause应该是只有selectedCat = 'Food'和selectedSubCat LIKE '%%' (ALL VALUES OF FIELD 'itemSubCategory' FOUND IN THE SQL TABLE)

第二种情况是用户仅选择Food并选择DropdownList值为Donut，这意味着查询语句的Where Clause应该只有selectedCat = 'Food' {1}}和selectedSubCat LIKE '%Donut%'

当用户点击Export to PDF按钮时，会执行这些代码行。 我删除了不必要的代码

  String itemCat = HF_TabListType.Value;
  String itemSubCatFood = ddlFood.SelectedValue;
  String itemSubCatBeverage = ddlBeverages.SelectedValue;

  //Retrieving Data to Populate to Report Table
  String strConnString = ConfigurationManager.ConnectionStrings["myConnectionString"].ConnectionString;
  SqlConnection myConn = new SqlConnection(strConnString);
  myConn.Open();

  SqlDataAdapter da;
  DataSet dsPDF = new DataSet();

  String retrieveQuery = String.Empty;

  using (System.IO.MemoryStream memoryStream = new System.IO.MemoryStream())
  {
      PdfPTable reportTable = new PdfPTable(1);
      if (itemCat == "Food" || itemCat == "Beverages")
      {
          reportTable = new PdfPTable(foodGV.Columns.Count - 1);
      }
      else if (itemCat == "Combo")
      {
          reportTable = new PdfPTable(gvCombo1Total.Columns.Count);
      }
      reportTable.TotalWidth = 1000f;
      reportTable.LockedWidth = true;
      reportTable.HorizontalAlignment = Element.ALIGN_CENTER;
      reportTable.SpacingAfter = 30f;

      //For Food and Beverages
      String[] headerForFB = { "No.", "Item Name", "Item Category", "Item Sub Category", "Item Price($)", "Orders", "Total($)" };

      //Fod Combo
      String[] headerForC = { "No.", "Combo", "Total Amount of Orders", "Total Discounts($)", "Total Sales($)" };

      if (itemCat == "Food" || itemCat == "Beverages")
      {
          for (int i = 0; i < headerForFB.Length; i++)
          {
              PdfPCell hCell = new PdfPCell(new Phrase(headerForFB[i].ToString(), BoldFontForHeader));
              hCell.FixedHeight = 25f;
              reportTable.AddCell(hCell);
          }
      }
      else if (itemCat == "Combo")
      {
          for (int i = 0; i < headerForC.Length; i++)
          {
              PdfPCell hCell = new PdfPCell(new Phrase(headerForC[i].ToString(), BoldFontForHeader));
              reportTable.AddCell(hCell);
          }
      }

      retrieveQuery = "SELECT itemName, itemCategory, itemSubCategory, itemPrice, orders, (orders * itemPrice) as TotalPrice FROM Menu WHERE itemCategory = @selectedCat AND itemSubCategory LIKE '%@selectedSubCat%'";

      da = new SqlDataAdapter(retrieveQuery.ToString(), myConn);
      da.SelectCommand.Parameters.AddWithValue("@selectedCat", itemCat);
      //da.SelectCommand.Parameters.AddWithValue("selectedSubCat", "%" + itemSubCatFood + "%");

      if (HF_TabListType.Value.ToString() == "Food")
      {
          if (ddlFood.SelectedIndex != 0)
          {
              da.SelectCommand.Parameters.AddWithValue("@selectedSubCat", itemSubCatFood);
          }
          else
          {
              da.SelectCommand.Parameters.AddWithValue("@selectedSubCat", "%%");
          }
      }
      else if (HF_TabListType.Value.ToString() == "Beverages")
      {
          if (ddlBeverages.SelectedIndex != 0)
          {
              da.SelectCommand.Parameters.AddWithValue("@selectedSubCat", itemSubCatBeverage);
          }
          else
          {
              da.SelectCommand.Parameters.AddWithValue("@selectedSubCat", "%%");
          }
      }

      da.Fill(dsPDF);

      GridView1.DataSource = dsPDF;
      GridView1.DataBind();

      PdfPCell cell = null;
      PdfPCell cellCount = null;
      int j = 0;

      //Food/Beverages
      if (dsPDF != null || dsPDF.Tables.Count != 0 || dsPDF.Tables[0].Rows.Count != 0)
      {
          foreach (DataRow r in dsPDF.Tables[0].Rows)
          {
              cellCount = new PdfPCell(new Phrase((j + 1).ToString(), NormalFont));
              cellCount.FixedHeight = 15f;
              reportTable.AddCell(cellCount);

              for (int i = 0; i < dsPDF.Tables[0].Columns.Count; i++)
              {
                  cell = new PdfPCell(new Phrase(r[i].ToString(), NormalFont));
                  cell.FixedHeight = 15f;
                  reportTable.AddCell(cell);
              }

              j++;
          }
      }

生成PDF时，PDF表的输出会给出这个..

使用上述Second Scenario，我试图修改代码，在某些情况下我得到2 rows with cells that are empty。这意味着生成的Dataset分别需要rows和columns来设置number of rows and columns的{{1}}。

检索声明是否存在问题？或者是因为在if else语句中添加了PDF Table行？

我一直试图解决这个问题......

感谢任何帮助，谢谢！

使用SQLDataAdapter清空数据集

0 个答案: