Custom Columns select using Crystal Report (Selected Columns to Be DISPLAYED IN CRYSTALREPORT AT RUN TIME)

First create a Data Set

Click on Add Button

It prompts for a message saying as

Click on Yes Button

ADD  YOUR COLUMNS  AS COLUMN1..........  COLUMNN

Add New Item

Select crystal report.rpt file and the below screen is visible

And Click on Ok button

And then press ctrl +alt +T

And click on  Ok BUTTON

In the Report Viewer Screen 

Press Ctrl+Alt +T 

In the Report 
Parameter Fields (Right Click and Select New)

Give the Name as col1

And Similarly Add 

Col2,col3,col4,

Similarly Add the Formula Fields as Below

And finally your database fields looks like 

Drag the controls 

.cs page

Add the following Namespaces

using CrystalDecisions.CrystalReports.Engine;

using CrystalDecisions.ReportSource;

using CrystalDecisions.Shared;

write the following code in button click

------------------------------------------------------------------------------------

private string GetData()

    {

        ReportDocument reportDocument;

        ParameterFields paramFields;

        ParameterField paramField;

        ParameterDiscreteValue paramDiscreteValue;

        reportDocument = new ReportDocument();

        paramFields = new ParameterFields();

        string query = "SELECT ";

        int columnNo = 0;

        if (ChkEmpID.Checked)

        {

            columnNo++;

            query = query.Insert(query.Length, "EmpID as Column" + columnNo.ToString());

            paramField = new ParameterField();

            paramField.Name = "col" + columnNo.ToString();

            paramDiscreteValue = new ParameterDiscreteValue();

            paramDiscreteValue.Value = "EmpID";

            paramField.CurrentValues.Add(paramDiscreteValue);

            //Add the paramField to paramFields

            paramFields.Add(paramField);

        }

        if (ChkEmpName.Checked)

        {

            columnNo++;

            if (query.Contains("Column"))

            {

                query = query.Insert(query.Length, ", ");

            }

            query = query.Insert(query.Length, "Ename as Column" + columnNo.ToString());

            paramField = new ParameterField();

            paramField.Name = "col" + columnNo.ToString();

            paramDiscreteValue = new ParameterDiscreteValue();

            paramDiscreteValue.Value = "Ename";

            paramField.CurrentValues.Add(paramDiscreteValue);

            //Add the paramField to paramFields

            paramFields.Add(paramField);

        }

        if (ChkDesignation.Checked)

        {

            columnNo++;

            if (query.Contains("Column"))

            {

                query = query.Insert(query.Length, ", ");

            }

            query = query.Insert(query.Length, "Designation as Column" + columnNo.ToString());

            paramField = new ParameterField();

            paramField.Name = "col" + columnNo.ToString();

            paramDiscreteValue = new ParameterDiscreteValue();

            paramDiscreteValue.Value = "Designation";

            paramField.CurrentValues.Add(paramDiscreteValue);

            //Add the paramField to paramFields

            paramFields.Add(paramField);

        }

        if (chksalary.Checked)

        {

            columnNo++;

            if (query.Contains("Column"))

            {

                query = query.Insert(query.Length, ", ");

            }

            query = query.Insert(query.Length, "Salary as Column" + columnNo.ToString());

            paramField = new ParameterField();

            paramField.Name = "col" + columnNo.ToString();

            paramDiscreteValue = new ParameterDiscreteValue();

            paramDiscreteValue.Value = "Salary";

            paramField.CurrentValues.Add(paramDiscreteValue);

            //Add the paramField to paramFields

            paramFields.Add(paramField);

        }

        CrystalReportViewer1.ParameterFieldInfo = paramFields;

        query += " FROM Employee";

        return query;

    }

 OUTPUT