String Reverse related questions in C# which is frequently ask in the interview

Q How to reverse a string in C# using predefined method ToCharArray()

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace ReverseStringConcept

{

class Program

{

static void Main(string[] args)

{

string strInput = null, strOutput = null;

Console.WriteLine("enter a string to revers");

strInput = Console.ReadLine();

char[] charInput = strInput.ToCharArray();

for (int i = charInput.Length-1; i >=0; i--)

{

strOutput = strOutput + strInput[i];

}

Console.WriteLine("reverse---->" + strOutput);

Console.ReadLine();

}

}

}

//ToCharaArray[]è

Copies the characters in this instance to a Unicode character array.

        //

        // Returns:

        //     A Unicode character array whose elements are the individual characters of

        //     this instance. If this instance is an empty string, the returned array is

        //     empty and has a zero length.

Q. How to reverse a string without any pre define function ?

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace ReverseStringConcept

{

class Program

{

static void Main(string[] args)

{

string strInput = null, strOutput = null;

int Length;

Console.WriteLine("enter a string to revers");

strInput = Console.ReadLine();

Length = strInput.Length - 1;

while (Length >= 0)

{

strOutput = strOutput + strInput[Length];

Length--;

}

Console.WriteLine("reverse   -->" + strOutput);

Console.ReadLine();

}

}

Output

Q Find given String is a palindrom or not?

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

            

namespace ReverseStringConcept

{

class Program

{

static void Main(string[] args)

{

string strInput = null, strOutput = null;

Console.WriteLine("enter a string to ");

strInput = Console.ReadLine();

char[] charInput = strInput.ToCharArray();

for (int i = charInput.Length- 1; i >= 0; i--)

{

strOutput = strOutput + charInput[i];

}

//Console.WriteLine(strInput);

//Console.WriteLine(strOutput);

if (strOutput == strInput)

{

Console.WriteLine("palindrom");

}

else

{

Console.WriteLine("Not a palindrom");

}

Console.ReadLine();

}

}

}

Output:

Q. Reverse  the string words  in the same position

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace ReverseStringConcept

{

class Program

{

static void Main(string[] args)

{

string strInput = null, strOutput = null;

Console.WriteLine("enter a string to ");

strInput = Console.ReadLine();

string[] words = strInput.Split(' ');

for (int i = 0; i <= words.Length-1; i++)

{

char[] charInput = words[i].ToCharArray();

for (int j = charInput.Length-1; j >=0; j--)

{

strOutput = strOutput + charInput[j];

}

strOutput += " ";

}

Console.WriteLine("reverse---->" + strOutput);

Console.ReadLine();

}

}

}

Output:

Read More

Paging, Sorting, Searching In ASP.NET by JQuery DataTable

Paging, Sorting, Searching In ASP.NET by JQuery DataTable

Nowadays   it is most popular way to apply client side searching, sorting and pagination (client/server side) through ajax/html request from any tabular format.

--Database.............................

USE [NORTHWND]

GO

/****** Object:  Table [dbo].[Customers]    Script Date: 26-11-2016 21:37:43 ******/

SET ANSI_NULLS ON

GO

SET QUOTED_IDENTIFIER ON

GO

CREATE TABLE [dbo].[Customers](

            [CustomerID] [nchar](5) NOT NULL,

            [CompanyName] [nvarchar](40) NOT NULL,

            [ContactName] [nvarchar](30) NULL,

            [ContactTitle] [nvarchar](30) NULL,

            [Address] [nvarchar](60) NULL,

            [City] [nvarchar](15) NULL,

            [Region] [nvarchar](15) NULL,

            [PostalCode] [nvarchar](10) NULL,

            [Country] [nvarchar](15) NULL,

            [Phone] [nvarchar](24) NULL,

            [Fax] [nvarchar](24) NULL,

 CONSTRAINT [PK_Customers] PRIMARY KEY CLUSTERED

(

            [CustomerID] ASC

)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]

) ON [PRIMARY]

GO

First we will take WebForm  in Asp.net Application which name is Default.aspx

Code for  Default.aspx.....................

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">

<head runat="server">

<title>JQuery Data Table in Asp.Net</title>

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>

<script src="https://cdn.datatables.net/1.10.12/js/jquery.dataTables.min.js"></script>

<link href="Style/bootstrap-theme.css" rel="stylesheet" />

<link href="Style/dataTables.jqueryui.css" rel="stylesheet" />

<link href="https://cdn.datatables.net/1.10.12/css/jquery.dataTables.min.css" rel="stylesheet" />

<script type="text/javascript">

$(document).ready(function () {

// Setup - add a text input to each footer cell

$('#example tfoot th').each(function () {

var title = $(this).text();

$(this).html('<input type="text" placeholder="Search ' + title + '" />');

});

// DataTable

var table = $('#example').DataTable();

// Apply the search

table.columns().every(function () {

var that = this;

$('input', this.footer()).on('keyup change', function () {

if (that.search() !== this.value) {

that

.search(this.value)

.draw();

}

});

});

});

</script>

<style type="text/css">

.paging_full_numbers span.paginate_button {

background-color: #fff;

}

.paging_full_numbers span.paginate_button:hover {

background-color: #ccc;

}

.paging_full_numbers span.paginate_active {

background-color: #99B3FF;

}

</style>

</head>

<body>

<form id="form1" runat="server">

<div style ="margin-top:30px">

<table class="table table-striped table-bordered " style="font-family: Serif;"

border="1px" id="example" >

<thead>

<tr>

<th>SrNo</th>

<th>CustomerID</th>

<th>CompanyName</th>

<th>Contact Name</th>

<th>Address</th>

<th>City</th>

<%-- <th> Region</th>

<th>PostalCode</th>

<th>Country</th>--%>

<th>Actions</th>

</tr>

</thead>

<tfoot>

<tr>

<th>SrNo</th>

<th>CustomerID</th>

<th>CompanyName</th>

<th>Contact Name</th>

<th>Address</th>

<th>City</th>

<%--<th> Region</th>

<th>PostalCode</th>

<th>Country</th>--%>

<th>Actions</th>

</tr>

</tfoot>

<tbody id="tlist" runat="server">

</tbody>

</table>

</div>

</form>

</body>

</html>

Code for  Default.aspx.cs.....................

using System;

using System.Collections.Generic;

using System.Data.SqlClient;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Configuration;

public partial class _Default : System.Web.UI.Page

{

protected void Page_Load(object sender, EventArgs e)

{

if (!IsPostBack)

{

BindDataTable();

}

}

SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["NORTHWNDConnectionString"].ConnectionString);

public void BindDataTable()

{

con.Open();

SqlCommand cmd = new SqlCommand("SELECT [CustomerID],[CompanyName],[ContactName],[ContactTitle],[Address],[City],[Region],[PostalCode],[Country],[Phone],[Fax]FROM[dbo].[Customers]", con);

SqlDataReader dr = cmd.ExecuteReader();

String result = "";

Int32 i = 1;

while (dr.Read())

{

result += "<tr>";

result += "                               <td>" +i.ToString() +"</td>";

result += "                               <td>" + dr["CustomerID"] + "</td>";

result += "                               <td>" + dr["CompanyName"] + "</td>";

result += "                               <td>" + dr["ContactName"] + "</td>";

result += "                               <td>" + dr["Address"] + "</td>";

result += "                               <td>" + dr["City"] + "</td>";

//result += "                            <td class=\"center\">" + dr["Region"] + "</td>";

//result += "                            <td class=\"center\">" + dr["PostalCode"] + "</td>";

//result += "                            <td class=\"center\">" + dr["Country"] + "</td>";

result += "                               <td class=\"center\">";

result += "                               <a class=\"btn btn-info\" href=\"Edit.aspx?ID=" + dr[0] + "\">";

result += "                               <i class=\"icon-edit icon-white\"></i>  ";

result += "                               Edit                                    ";

result += "                               </a>";

result += "                   <a class=\"btn btn-info\" href=\"Delete.aspx?ID=" + dr[0] + "\">";

result += "                   <i class=\"icon-edit icon-white\"></i>  ";

result += "                                                       Delete                                    ";

result += "                                           </a>";

result += "                               </td>";

result += "                   </tr>";

tlist.InnerHtml = result;

i++;

}

con.Close();

}

}

Result

<!DOCTYPE html>
<html>
<head>
    <title></title>
    <meta charset="utf-8" />

    <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
    <script src="https://cdn.datatables.net/1.10.12/js/jquery.dataTables.min.js"></script>


    <link href="https://cdn.datatables.net/1.10.12/css/jquery.dataTables.min.css" rel="stylesheet" />
    <style type="text/css">
        tfoot input {
            width: 100%;
            padding: 3px;
            box-sizing: border-box;
        }
    </style>

   

  
    <script type="text/javascript">

        $(document).ready(function () {
            // Setup - add a text input to each footer cell
            $('#example tfoot th').each(function () {
                var title = $(this).text();
                $(this).html('<input type="text" placeholder="Search ' + title + '" />');
            });

            // DataTable
            var table = $('#example').DataTable();

            // Apply the search
            table.columns().every(function () {
                var that = this;

                $('input', this.footer()).on('keyup change', function () {
                    if (that.search() !== this.value) {
                        that
                            .search(this.value)
                            .draw();
                    }
                });
            });
        });
    </script>
</head>
<body>
    <table id="example" class="display" cellspacing="0" width="100%">
        <thead>
            <tr>
                <th>Name</th>
                <th>Position</th>
                <th>Office</th>
                <th>Age</th>
                <th>Start date</th>
                <th>Salary</th>
            </tr>
        </thead>
        <tfoot>
            <tr>
                <th>Name</th>
                <th>Position</th>
                <th>Office</th>
                <th>Age</th>
                <th>Start date</th>
                <th>Salary</th>
            </tr>
        </tfoot>
        <tbody>
            <tr>
                <td>Kush Tiwari</td>
                <td>.Net Developer</td>
                <td>Hard Shell Pvt Ltd</td>
                <td>29</td>
                <td>2016/11/24</td>
                <td>50000</td>
            </tr>

            <tr>
                <td>Udayan Maiti</td>
                <td>Sr .Net Developer</td>
                <td>Hard Shell Pvt Ltd</td>
                <td>31</td>
                <td>2015/11/24</td>
                <td>67000</td>
            </tr>

........................................................

............................................
            </tbody>
    </table>
</body>
</html>













 

Read More