如何改变使用C＃的Excel单元格的格式

IHI我正在尝试读取平面文件n以优秀。 我能够使用数据表生成Excel文件，但date字段显示为#####。 我正在尝试更改单元格的格式，但无法达到此目的。 我已经添加了代码以供参考。 请引导我，因为我需要从这个生成的表格与公式一起创build另一个工作表。 最有趣的事情是我看到date

在这张表上，但如果我复制这些数据在另一张纸上，我可以看到date字段，而不是#####。

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data; using System.IO; using Microsoft.Office.Interop.Excel; using System.Threading.Tasks; using System.Reflection; namespace report { class Program { static void Main(string[] args) { string path = @"flat.txt"; //Flat file System.Data.DataTable table = ReadFile(path); Excel_FromDataTable(table); } private static System.Data.DataTable ReadFile(string path) { System.Data.DataTable table = new System.Data.DataTable("dataFromFile"); DataColumn colu; for (int i = 0; i < 250; i++) { colu = new DataColumn("", System.Type.GetType("System.String")); colu.AllowDBNull = true; table.Columns.Add(colu); } using (StreamReader sr = new StreamReader(path)) { string line; int rowsCount = 0; while ((line = sr.ReadLine()) != null) { string[] data = line.Split(new string[] { "|" },StringSplitOptions.None);// Separated by delimiter | table.Rows.Add(); for (int i = 0; i < data.Length; i++) { //if (data[i].Contains("")) //if (data[i].Equals("")) // table.Rows[rowsCount][i] = "---"; // data[i] = " "; if (!data[i].Equals("")) table.Rows[rowsCount][i] = data[i]; } rowsCount++; } } return table; } private static void Excel_FromDataTable(System.Data.DataTable dt) { //create an excel object and add to a work book.... Application excel = new Application(); //check if you can use ApplicationClass Workbook workbook = excel.Application.Workbooks.Add(true); //add coulmn heading... int iCol = 0; foreach (DataColumn c in dt.Columns) { iCol++; excel.Cells[1, iCol] = c.ColumnName; } //add row int iRow = 0; foreach (DataRow r in dt.Rows) { iRow++; //add each row's cell data... iCol = 0; foreach (DataColumn c in dt.Columns) { iCol++; excel.Cells[iRow + 1, iCol] = r[c.ColumnName]; } } //Globalmissing refernce for objects we are not defining... object missing = System.Reflection.Missing.Value; //excel.get_Range("C3", iRow).NumberFormat = "mm/dd/yyyy"; workbook.SaveAs(@"C:/report.xls", XlFileFormat.xlXMLSpreadsheet, missing, missing, false, false, XlSaveAsAccessMode.xlExclusive, missing, missing, missing, missing, missing); // If wanting to make Excel visible and activate the worksheet excel.Visible = true; } } } Excel file is like this Column1 Column2 Column3 AAA ######### 103 D-1 17 ######## D-2 17 ######## D-3 17 ######## 

Answer 1

date字段显示为######，因为date比列长。 尝试重新调整列的大小。

 sheet.Columns.AutoFit(); 

另请尝试：

 sheet.Cells[row, column] = String.Format("{0:MM/dd/yyyy}", object.DateEntered); 

已更新答案：

  int iRow = 0; foreach (DataRow r in dt.Rows) { iRow++; //add each row's cell data... iCol = 0; foreach (DataColumn c in dt.Columns) { iCol++; try { DateTime date = Convert.ToDateTime(r[c.ColumnName]); excel.Cells[iRow + 1, iCol] = String.Format("{0:MM/dd/yyyy", date); } catch(Exception e) { excel.Cells[iRow + 1, iCol] = r[c.ColumnName]; } } } 

Answer 2

这里是我写的一个简单的方法，将任何DataTable转换为CSV

 //Declared at the class Level private const string tableDelim = "|"; private static DataTable GetDataTabletFromCSVFile(string csv_file_path) { csvData = new DataTable(defaultTableName); try { using (TextFieldParser csvReader = new TextFieldParser(csv_file_path)) { csvReader.SetDelimiters(new string[] { //this will be a constant declared at the class level private const string tableDelim = ","; tableDelim }); csvReader.HasFieldsEnclosedInQuotes = true; string[] colFields = csvReader.ReadFields(); foreach (string column in colFields) { DataColumn datecolumn = new DataColumn(column); datecolumn.AllowDBNull = true; csvData.Columns.Add(datecolumn); } while (!csvReader.EndOfData) { string[] fieldData = csvReader.ReadFields(); //Making empty value as null for (int i = 0; i < fieldData.Length; i++) { if (fieldData[i] == string.Empty) { fieldData[i] = string.Empty; //fieldData[i] = null } //Skip rows that have any csv header information or blank rows in them if (fieldData[0].Contains("Disclaimer") || string.IsNullOrEmpty(fieldData[0])) { continue; } } csvData.Rows.Add(fieldData); } } } catch (Exception ex) { //write your own Exception Messaging here } return csvData; } 

转换.CSV文件并保存为.XLS格式这里是一个很好的从Stackoverflow的简单参考以及将ExcelFile .CSV转换为.XLS格式