在數據表中追加記錄

Question

我已經在其他地方發佈了這個記錄，但是我對該要求的理解對於主持人@ShaiCohen來說是不正確的，他幫助我建議我重新發布它。

我需要編輯提供給DataTable的數據，這些數據可能有不同的列和行，但前兩列是固定的。 （在該行的開頭數字是不是數據的一部分）的數據是這樣的：

Repair Repair 
    Code Code Entries   6/1/2012 7/1/2012 8/1/2012 9/1/2012 
    ------ -------------------- -------- -------- -------- -------- 
1. 00000A Critical Down Time  1  
2. 00000A Critical Outage   1  
3. 00000A Total Repair Time  65   
4. 00000B Critical Down Time          6 
5. 00000B Total Repair Time          90 
6. 00000C Critical Down Time  1   5  
7. 00000C Critical Outage   1   5  
8. 00000C Total Repair Time  30   240  
9. 00000D Critical Down Time          2  
10. 00000E Critical Down Time       1  
11. 00000G Critical Down Time          1  
12. 00000M Critical Down Time  1       3  
13. 00000M Critical Outage   1     3  
14. 00000M Total Repair Time   60    180 

注意線1-3，6-8，具有相同的維修代碼分類，並因此被視爲組。另一方面，第10-12行只有「臨界停機時間」子類別，而其餘的則是三者的組合。

要求是將「修理代碼條目」子類別插入不存在的地方。他們不存在的原因是因爲數據庫中沒有數據，但客戶希望看到即使沒有相應的數據也顯示缺少的字母，並插入空行來分隔這些組：

Repair Repair 
    Code Code Entries   6/1/2012 7/1/2012 8/1/2012 9/1/2012 
    ------ -------------------- -------- -------- -------- -------- 
1. 00000A Critical Down Time  1  
2. 00000A Critical Outage   1  
3. 00000A Total Repair Time  65   

4. 00000B Critical Down Time          6 
    00000B Critical Outage   
5. 00000B Total Repair Time          90 

6. 00000C Critical Down Time  1   5  
7. 00000C Critical Outage   1   5  
8. 00000C Total Repair Time  30   240 

9. 00000D Critical Down Time          2 
    00000D Critical Outage   
    00000D Total Repair Time   

當然，這是目前實行的代碼假定數據始終三個子類別等的分組時，它是沒有那麼從上一行的子類別在將當前行中的子類別：

8. 00000C Total Repair Time  30   240 

9. 00000D Total Repair Time (should be Critical Down Time)  2 
    00000D Critical Outage   

在代碼中（下面）subCategoryOccurences裏面的CheckSubCategoryRequirements方法沒有得到rese當新行被處理時，t爲零。

public void PrepareDataTable(DataTable dtResults) 
{ 

    if (dtResults == null || dtResults.Rows.Count == 0) 
     return; 

    //initialize category 
    categoryPrevious = dtResults.Rows[0]["Category"].ToString(); 
    do 
    { 
     //get the current category 
     categoryCurrent = dtResults.Rows[rowCount]["Category"].ToString(); 
     //check if this is a new category. this is where all the work is done 
     if (categoryCurrent != categoryPrevious) 
     { 
      //check if we have fulfilled the requirement for number of subcategories 
      CheckSubCategoryRequirements(dtResults); 
      //at this point we have fulfilled the requirement for number of subcategories 
      //add blank (separator) row 
      dtResults.Rows.InsertAt(dtResults.NewRow(), rowCount); 
      rowCount++; 
      //reset the number of subcategories 
      subCategoryOccurences = 0; 
      categoryPrevious = categoryCurrent; 
     } 
     else 
     { 
      rowCount++; 
      categoryOccurences++; 
     } 
    } while (rowCount < dtResults.Rows.Count); 
    //check sub category requirements for the last category 
    CheckSubCategoryRequirements(dtResults); 
} 




private void CheckSubCategoryRequirements(DataTable dtResults) 
{ 
    if (subCategoryOccurences< subCategories.Length) 
    { 
     //we need to add rows for the missing subcategories 
     while (subCategoryOccurences< subCategories.Length) 
     { 
      //create a new row and populate category and subcategory info 
      rowFiller = dtResults.NewRow(); 
      rowFiller["Category"] = categoryPrevious; 
      rowFiller["SubCategory"] = subCategories[subCategoryOccurences]; 
      //insert the new row into the current location of table 
      dtResults.Rows.InsertAt(rowFiller, rowCount); 
      subCategoryOccurences++; 
      rowCount++; 
     } 
    } 
} 

我試圖在方法調用之前移動計數器，但導致了不希望的結果，所以我不確定從這裏去哪裏。我會很感激建設性的意見。謝謝。 R.

Answer 1

對於這些要求，我採取了與以前不同的方法。有了這些新的要求，我們將不得不「倒退」插入先前缺失的子類別。

此方法創建一個新的表，該表填充了原始表中存在的每個類別的正確數量的子類別。一旦新行被創建，我們然後檢查舊的表，以查看是否有任何數據需要複製到新表表（即：「6/1/2012」和「2012年7月1日」 「從你的例子）。

試試這個代碼：

public DataTable PrepareDataTable(DataTable dtResults) 
{ 
    string[] subCategories = new string[3] {"Critical Down Time", "Critical Outage", "Total Repair Time"}; 
    //make a copy of the original table 
    DataTable dtOutput = dtResults.Clone(); 
    DataRow drOutput = null; 
    DataRow[] drResults = null; 
    //retrieve the list of Categories 
    var categories = dtResults.AsEnumerable().Select(r => r["Category"]).Distinct().ToList(); 
    //populate the new table with the appropriate rows (combinations of categories/subcategories) 
    foreach (string category in categories) 
    { 
     for (int i = 0; i < subCategories.Length ; i++) 
     { 
      //create the new row in the new table 
      drOutput = dtOutput.NewRow(); 
      drOutput["Category"] = category; 
      drOutput["SubCategory"] = subCategories[i]; 
      //here is where you will check to see if a row with the same category and subcategory exists in dtResults. if it does, then copy over the values for each column 
      drResults = dtResults.Select(String.Format("Category = '{0}' AND SubCategory = '{1}'", category, subCategories[i])); 
      if(drResults.Length > 0) 
      { 
       foreach(DataColumn column in dtResults.Columns) 
       { 
        drOutput[column.ColumnName] = drResults[0][column.ColumnName]; 
       } 

      } 
      dtOutput.Rows.Add(drOutput); 
     } 
     //add filler/spacer row 
     drOutput = dtOutput.NewRow(); 
     dtOutput.Rows.Add(drOutput); 
    } 
    return dtOutput; 
} 

這裏是 「測試工具」：

public void RunTest() 
{ 
    DataTable dtResults = new DataTable(); 
    dtResults.Columns.Add("Category"); 
    dtResults.Columns.Add("SubCategory"); 
    dtResults.Columns.Add("Data"); 
    dtResults.Rows.Add("00000A", "Critical Down Time", "1"); 
    dtResults.Rows.Add("00000A", "Critical Outage", "1"); 
    dtResults.Rows.Add("00000A", "Total Repair Time", "1"); 
    dtResults.Rows.Add("00000B", "Critical Down Time", "1"); 
    dtResults.Rows.Add("00000B", "Total Repair Time", "1"); 
    dtResults.Rows.Add("00000C", "Critical Down Time", "1"); 
    dtResults.Rows.Add("00000C", "Critical Outage", "1"); 
    dtResults.Rows.Add("00000C", "Total Repair Time", "1"); 
    dtResults.Rows.Add("00000D", "Critical Down Time", "1"); 
    dtResults.Rows.Add("00000E", "Critical Down Time", "1"); 
    dtResults.Rows.Add("00000G", "Critical Down Time", "1"); 
    dtResults.Rows.Add("00000M", "Critical Down Time", "1"); 
    dtResults.Rows.Add("00000M", "Critical Outage", "1"); 
    dtResults.Rows.Add("00000M", "Total Repair Time", "1"); 
    DataTable dtOutput = PrepareDataTable(dtResults); 
}