如何快速的将 DataTable 导入到 Excel 中 ？

Posted 2022-07-24 biyusr216

咨询区

• user1334858

我尝试将 ​​DataTable​​​ 导入到 ​​Excel​​​ 中，但我目前的方法性能太差，可能是因为我逐个 ​​WorkSheet​​​，​​Cell​​ 去处理导致，下面是我的代码：

    List<DataTable> List = new List<DataTable>();

    // Counting sheets
    for (int count = 1; count < WB.Worksheets.Count; ++count)
    
        // Create a new DataTable for every Worksheet
        DATA.DataTable DT = new DataTable();

        WS = (EXCEL.Worksheet)WB.Worksheets.get_Item(count);

        textBox1.Text = count.ToString();

        // Get range of the worksheet
        Range = WS.UsedRange;


        // Create new Column in DataTable
        for (cCnt = 1; cCnt <= Range.Columns.Count; cCnt++)
        
            textBox3.Text = cCnt.ToString();


                Column = new DataColumn();
                Column.DataType = System.Type.GetType("System.String");
                Column.ColumnName = cCnt.ToString();
                DT.Columns.Add(Column);

            // Create row for Data Table
            for (rCnt = 0; rCnt <= Range.Rows.Count; rCnt++)
            
                textBox2.Text = rCnt.ToString();

                try
                
                    cellVal = (string)(Range.Cells[rCnt, cCnt] as EXCEL.Range).Value2;
                
                catch (Microsoft.CSharp.RuntimeBinder.RuntimeBinderException)
                
                    ConvertVal = (double)(Range.Cells[rCnt, cCnt] as EXCEL.Range).Value2;
                    cellVal = ConvertVal.ToString();
                

                // Add to the DataTable
                if (cCnt == 1)
                

                    Row = DT.NewRow();
                    Row[cCnt.ToString()] = cellVal;
                    DT.Rows.Add(Row);
                
                else
                

                    Row = DT.Rows[rCnt];
                    Row[cCnt.ToString()] = cellVal;

                
            
        
        // Add DT to the list. Then go to the next sheet in the Excel Workbook
        List.Add(DT);
    

请问是否有更快的处理办法？

回答区

• D Stanley

调用 ​​.Value2​​​ 因为涉及到 ​​COM​​​ 互操作，所以它是一个开销很大的动作，你应该一次性读取一个 ​​范围​​​ 到 数组中， 然后再遍历这个 ​​数组​​，参考如下代码：

object[,] data = Range.Value2;

// Create new Column in DataTable
for (int cCnt = 1; cCnt <= Range.Columns.Count; cCnt++)

    textBox3.Text = cCnt.ToString();

    var Column = new DataColumn();
    Column.DataType = System.Type.GetType("System.String");
    Column.ColumnName = cCnt.ToString();
    DT.Columns.Add(Column);

    // Create row for Data Table
    for (int rCnt = 1; rCnt <= Range.Rows.Count; rCnt++)
    
        textBox2.Text = rCnt.ToString();

        string CellVal = String.Empty;
        try
        
            cellVal = (string)(data[rCnt, cCnt]);
        
        catch (Microsoft.CSharp.RuntimeBinder.RuntimeBinderException)
        
            ConvertVal = (double)(data[rCnt, cCnt]);
            cellVal = ConvertVal.ToString();
        

        DataRow Row;

        // Add to the DataTable
        if (cCnt == 1)
        

            Row = DT.NewRow();
            Row[cCnt.ToString()] = cellVal;
            DT.Rows.Add(Row);
        
        else
        

            Row = DT.Rows[rCnt + 1];
            Row[cCnt.ToString()] = cellVal;

        
    
 

总的来说，​​MS Office Interop​​​ 本身就很慢，其实微软自己也不推荐用这个方式，也不能用来导入大 Excel 文件，更多细节可参考：​​https://support.microsoft.com/en-us/topic/considerations-for-server-side-automation-of-office-48bcfe93-8a89-47f1-0bce-017433ad79e2​​

所以我个人建议，你应该使用 ​​EasyXLS​​​ 或者 ​​EditPlus​​ 这样的第三方库。

点评区

现实开发中，用微软的 ​​MS Office Interop​​​ 去操控 Excel 的确实比较少，貌似还要在本机安装 ​​Office365​​​, 用 ​​EditPlus​​ 就好啦。