How to preserve data types during ImportDataTable in C#, VB.NET?
This article explains how to preserve data types while importing DataTable to worksheet.
While importing a DataTable to a worksheet using XlsIO, the data types can be preserved by setting the data type of column with values in the DataTable as string and preserveTypes as true in ImportDataTable method.
Code snippet to preserve a data types while importing DataTable to worksheet
//Importing a DataTable to Worksheet worksheet.ImportDataTable(dt, true, 1, 1, -1, -1, true);
To know more about importing and exporting data, please refer the documentation.
The following C#/VB complete code snippet illustrates how to preserve data types while importing DataTable to worksheet.
C#
using System; using System.Data; using System.IO; using Syncfusion.XlsIO; namespace PreserveLongNumber { class Program { static void Main(string[] args) { using (ExcelEngine excelEngine = new ExcelEngine()) { IApplication application = excelEngine.Excel; application.DefaultVersion = ExcelVersion.Excel2013; //Create new workbook IWorkbook workbook = application.Workbooks.Create(1); //Accessing first worksheet in the workbook IWorksheet worksheet = workbook.Worksheets[0]; //Creating a DataTable to import DataTable dt = new DataTable(); dt.Columns.Add("Name", typeof(string)); dt.Columns.Add("Number", typeof(long)); dt.Columns.Add("StringNumber", typeof(string)); dt.Columns.Add("StringDate", typeof(string)); dt.Columns.Add("Date", typeof(DateTime)); DataRow dr1 = dt.NewRow(); dr1["Name"] = "aaa"; dr1["Number"] = 6755510089231745873; dr1["StringNumber"] = "6755510089231745873"; dr1["Date"] = DateTime.Now.ToString(); dr1["StringDate"] = DateTime.Now.ToString(); dt.Rows.Add(dr1); DataRow dr2 = dt.NewRow(); dr2["Name"] = "bbb"; dr2["Number"] = 6755510089231745873; dr2["StringNumber"] = "6755510089231745873"; dr2["Date"] = DateTime.Now.ToString(); dr2["StringDate"] = DateTime.Now.ToString(); dt.Rows.Add(dr2); DataRow dr3 = dt.NewRow(); dr3["Name"] = "ccc"; dr3["Number"] = 6755510089231745873; dr3["StringNumber"] = "6755510089231745873"; dr3["Date"] = DateTime.Now.ToString(); dr3["StringDate"] = DateTime.Now.ToString(); dt.Rows.Add(dr3); //Importing a DataTable to Worksheet worksheet.ImportDataTable(dt, true, 1, 1, -1, -1, true); //Save the workbook as stream Stream stream = File.Create("Output.xlsx"); workbook.SaveAs(stream); } } } }
VB
Imports Syncfusion.XlsIO Imports System Imports System.Data Imports System.IO Namespace PreserveLongNumber Class Program Private Shared Sub Main(ByVal args() As String) Using excelEngine As ExcelEngine = New ExcelEngine Dim application As IApplication = excelEngine.Excel application.DefaultVersion = ExcelVersion.Excel2013 'Create new workbook Dim workbook As IWorkbook = application.Workbooks.Create(1) 'Accessing first worksheet in the workbook Dim worksheet As IWorksheet = workbook.Worksheets(0) 'Creating a DataTable to import Dim dt As DataTable = New DataTable dt.Columns.Add("Name", GetType(System.String)) dt.Columns.Add("Number", GetType(System.Int64)) dt.Columns.Add("StringNumber", GetType(System.String)) dt.Columns.Add("StringDate", GetType(System.String)) dt.Columns.Add("Date", GetType(DateTime)) Dim dr1 As DataRow = dt.NewRow dr1("Name") = "aaa" dr1("StringNumber") = "6755510089231745873" dr1("Date") = DateTime.Now.ToString dr1("StringDate") = DateTime.Now.ToString dt.Rows.Add(dr1) Dim dr2 As DataRow = dt.NewRow dr2("Name") = "bbb" dr2("StringNumber") = "6755510089231745873" dr2("Date") = DateTime.Now.ToString dr2("StringDate") = DateTime.Now.ToString dt.Rows.Add(dr2) Dim dr3 As DataRow = dt.NewRow dr3("Name") = "ccc" dr3("StringNumber") = "6755510089231745873" dr3("Date") = DateTime.Now.ToString dr3("StringDate") = DateTime.Now.ToString dt.Rows.Add(dr3) 'Importing a DataTable to Worksheet worksheet.ImportDataTable(dt, True, 1, 1, -1, -1, True) 'Save the workbook as stream Dim stream As Stream = File.Create("Output.xlsx") workbook.SaveAs(stream) End Using End Sub End Class End Namespace