Export Dataset/Datatable to CSV File Using C# and VB.NET

Introduction

Export Dataset/Datatable to CSV File Using C# and VB.NET

Requirement

Implementation

C#

DataTable GetData()
       {
           DataTable dt = new DataTable();
           dt.Columns.Add("CustomerId", typeof(int));
           dt.Columns.Add("CustomerName", typeof(string));
           dt.Columns.Add("ProductName", typeof(string));
           dt.Columns.Add("Price", typeof(double));
           dt.Rows.Add(1, "Nikunj Satasiya", "Laptop", 37000);
           dt.Rows.Add(2, "Hiren Dobariya", "Mouse", 820);
           dt.Rows.Add(3, "Vivek Ghadiya", "Pen", 250);
           dt.Rows.Add(4, "Pratik Pansuriya", "Laptop", 42000);
           dt.Rows.Add(5, "Sneha Patel", "Lip Bam", 130);
           dt.Rows.Add(6, "Jhon Smith", "Sigar", 150);
           return dt;
       }

VB

Private Function GetData() As DataTable
        Dim dt As DataTable = New DataTable
        dt.Columns.Add("CustomerId", GetType(System.Int32))
        dt.Columns.Add("CustomerName", GetType(System.String))
        dt.Columns.Add("ProductName", GetType(System.String))
        dt.Columns.Add("Price", GetType(System.Double))
        dt.Rows.Add(1, "Nikunj Satasiya", "Laptop", 37000)
        dt.Rows.Add(2, "Hiren Dobariya", "Mouse", 820)
        dt.Rows.Add(3, "Vivek Ghadiya", "Pen", 250)
        dt.Rows.Add(4, "Pratik Pansuriya", "Laptop", 42000)
        dt.Rows.Add(5, "Sneha Patel", "Lip Bam", 130)
        dt.Rows.Add(6, "Jhon Smith", "Sigar", 150)
        Return dt
    End Function

Datatable

Now We will write a custom function/method to write csv file. 

C#

public static string WriteCSV(string input)
        {
            try
            {
                if (input == null)
                    return string.Empty;
 
                bool containsQuote = false;
                bool containsComma = false;
                int len = input.Length;
                for (int i = 0; i < len && (containsComma == false || containsQuote == false); i++)
                {
                    char ch = input[i];
                    if (ch == '"')
                        containsQuote = true;
                    else if (ch == ',')
                        containsComma = true;
                }
 
                if (containsQuote && containsComma)
                    input = input.Replace("\"", "\"\"");
 
                if (containsComma)
                    return "\"" + input + "\"";
                else
                    return input;
            }
            catch
            {
                throw;
            }
        }

VB

Public Shared Function WriteCSV(ByVal input As String) As String
        Try
            If (input Is Nothing) Then
                Return String.Empty
            End If
 
            Dim containsQuote As Boolean = False
            Dim containsComma As Boolean = False
            Dim len As Integer = input.Length
            Dim i As Integer = 0
            Do While ((i < len) _
                        AndAlso ((containsComma = False) _
                        OrElse (containsQuote = False)))
                Dim ch As Char = input(i)
                If (ch = Microsoft.VisualBasic.ChrW(34)) Then
                    containsQuote = True
                ElseIf (ch = Microsoft.VisualBasic.ChrW(44)) Then
                    containsComma = True
                End If
 
                i = (i + 1)
            Loop
 
            If (containsQuote AndAlso containsComma) Then
                input = input.Replace(""""", ", """"")", if, (containsCommaUnknown, """"" + input + ", "")
            Else
                Return input
            End If
 
        Catch  As System.Exception
            Throw
        End Try
 
    End Function

C#

private void btnCSV_Click(object sender, EventArgs e)
        {
            StringBuilder sb = new StringBuilder();
            DataTable dt = GetData();
            foreach (DataRow dr in dt.Rows)
            {
                foreach (DataColumn dc in dt.Columns)
                    sb.Append(WriteCSV(dr[dc.ColumnName].ToString()) + ",");
                sb.Remove(sb.Length - 1, 1);
                sb.AppendLine();
            }
            File.WriteAllText(@"C:\Users\Nikunj-PC\Desktop\Demo\CodingvilaCSV.csv", sb.ToString());
            lblMsg.Text = "Successful";
        }

VB

Private Sub btnCSV_Click(ByVal sender As Object, ByVal e As EventArgs)
        Dim sb As StringBuilder = New StringBuilder
        Dim dt As DataTable = GetData
        For Each dr As DataRow In dt.Rows
            For Each dc As DataColumn In dt.Columns
                sb.Append((WriteCSV(dr(dc.ColumnName).ToString) + ","))
            Next
            sb.Remove((sb.Length - 1), 1)
            sb.AppendLine()
        Next
        File.WriteAllText("C:\Users\Nikunj-PC\Desktop\Demo\CodingvilaCSV.csv", sb.ToString)
        lblMsg.Text = "Successful"
    End Sub

Visualizer

OutPut

CSV File

Summary