In usual practice , Crystal Reports we are getting from pre defined columns. But we can make Crystal Reports from Dynamic column . Here we are going to do the dynamic Crystal Reports from SQL statements . That is we enter SQL in textbox and get the Crystal Reports according to the SQL statement.
All Crystal Reports programming samples in this tutorials is based on the following database (crystaldb) . Please take a look at the database structure before you start this tutorial - Click here to see Database Structure .
Create a new VB.NET project and add a Strongly Typed Dataset . Before creating a Strongly Typed take a look at the detailed tutorial of create a strongly typed datset and add five column in the Datatable. Here we are limiting as five column , but you can add any number of column according to your requirements.
Next step is to create a Crystal Reports design from the Strongly Typed dataset.
Select all the column from dataset.
Select the default form(Form1.vb) and add a TextBox , Button and Crystal Reports Viewer .
Here we are going to pass the SQl statements to Crystal Reports at runtime . For that we parsing the SQL statement before we passing it to Crystal Reports. So we create a function for parsing SQL statements.
Public Function procesSQL() As String
Put the following vb.net source code in your form and run the program .
Imports System.Data.SqlClient Imports CrystalDecisions.CrystalReports.Engine Imports CrystalDecisions.Shared Imports System.Data Public Class Form1 Dim objRpt As New CrystalReport1 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim cnn As SqlConnection Dim connectionString As String Dim sql As String connectionString = "data source=SERVERNAME; _ initial catalog=crystaldb;user id=sa;password=PASSWORD;" cnn = New SqlConnection(connectionString) cnn.Open() sql = procesSQL() Dim dscmd As New SqlDataAdapter(sql, cnn) Dim ds As New DataSet1 dscmd.Fill(ds, "Product") objRpt.SetDataSource(ds.Tables(1)) CrystalReportViewer1.ReportSource = objRpt CrystalReportViewer1.Refresh() End Sub Public Function procesSQL() As String Dim sql As String Dim inSql As String Dim firstPart As String Dim lastPart As String Dim selectStart As Integer Dim fromStart As Integer Dim fields As String() Dim i As Integer Dim MyText As TextObject inSql = TextBox1.Text inSql = inSql.ToUpper selectStart = inSql.IndexOf("SELECT") fromStart = inSql.IndexOf("FROM") selectStart = selectStart + 6 firstPart = inSql.Substring(selectStart, (fromStart - selectStart)) lastPart = inSql.Substring(fromStart, inSql.Length - fromStart) fields = firstPart.Split(",") firstPart = "" For i = 0 To fields.Length - 1 If i > 0 Then firstPart = firstPart & " , " _ & fields(i).ToString() & " AS COLUMN" & i + 1 MyText = CType(objRpt.ReportDefinition.ReportObjects("Text" _ & i + 1), TextObject) MyText.Text = fields(i).ToString() Else firstPart = firstPart & fields(i).ToString() & _ " AS COLUMN" & i + 1 MyText = CType(objRpt.ReportDefinition.ReportObjects("Text" & _ i + 1), TextObject) MyText.Text = fields(i).ToString() End If Next sql = "SELECT " & firstPart & " " & lastPart Return sql End Function End Class
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