Compare two strings and highlight changes using C# and VB.Net in ASP.Net

Hi naresh1994,

Refer below sample.

Use regular expression and stringcollection check whether words are containing or not.

Refer below sample for better understand.

HTML

<asp:Label ID="lblMessage" runat="server" />

Namespaces

C#

using System.Collections.Specialized;

VB.Net

Imports System.Collections.Specialized

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    string message1 = "Mr. Dhinna's broad international experience provides the board of directors with his unique insights related to Blockbuster strategy, operations and business";
    message1 += "as a global company. Mr. Dhinna brings to the board significant commercial transaction experience from his Kissinger Associates role till 25/06/2016, as well as domestic and";
    message1 += "international public policy experience. Mr. Dhinna has extensive knowledge in a number of important areas, including innovative problem-solving related to";
    message1 += "global risks and opportunities, particularly with regard to China and Japan. He is also ex CFO of ABC Inc.";

    string message2 = "Mr. Dhinna's broad international experience provides the board of directors with his unique insights related to Blockbuster strategy, operations and business";
    message2 += "as a global company. Mr. Dhinna brings to the board significant commercials transaction less experience from his Kissinger Associates role till 25/06/2018, as well as domestic and";
    message2 += "international public policy experience. Mr. Dhinna has extensive knowledge in a number of important areas, including innovative problem-solving could not be to";
    message2 += "global risks and opportunities, particularly with regard to China and Japan. He is also ex CFO of ABC Inc.";
    StringCollection stringCollectionmessage1 = new StringCollection();
    StringCollection stringCollectionmessage2 = new StringCollection();
    stringCollectionmessage1.AddRange(System.Text.RegularExpressions.Regex.Split(message1, @"\b(\w+)(\W){1,2}"));
    stringCollectionmessage2.AddRange(System.Text.RegularExpressions.Regex.Split(message2, @"\b(\w+)(\W){1,2}"));
    for (int i = 0; i < stringCollectionmessage1.Count; i++)
    {
        if (!stringCollectionmessage1.Contains(stringCollectionmessage2[i]))
        {
            lblMessage.Text += "<font color='Red'>" + stringCollectionmessage2[i].ToString() + "</font>" + " ";
        }
        else
        {
            lblMessage.Text += stringCollectionmessage1[i].ToString() + " ";
        }
    }
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)Handle Me.Load
    Dim message1 As String = "Mr. Dhinna's broad international experience provides the board of directors with his unique insights related to Blockbuster strategy, operations and business"
    message1 += "as a global company. Mr. Dhinna brings to the board significant commercial transaction experience from his Kissinger Associates role till 25/06/2016, as well as domestic and"
    message1 += "international public policy experience. Mr. Dhinna has extensive knowledge in a number of important areas, including innovative problem-solving related to"
    message1 += "global risks and opportunities, particularly with regard to China and Japan. He is also ex CFO of ABC Inc."
    Dim message2 As String = "Mr. Dhinna's broad international experience provides the board of directors with his unique insights related to Blockbuster strategy, operations and business"
    message2 += "as a global company. Mr. Dhinna brings to the board significant commercials transaction less experience from his Kissinger Associates role till 25/06/2018, as well as domestic and"
    message2 += "international public policy experience. Mr. Dhinna has extensive knowledge in a number of important areas, including innovative problem-solving could not be to"
    message2 += "global risks and opportunities, particularly with regard to China and Japan. He is also ex CFO of ABC Inc."
    Dim stringCollectionmessage1 As StringCollection = New StringCollection()
    Dim stringCollectionmessage2 As StringCollection = New StringCollection()
    stringCollectionmessage1.AddRange(System.Text.RegularExpressions.Regex.Split(message1, "\b(\w+)(\W){1,2}"))
    stringCollectionmessage2.AddRange(System.Text.RegularExpressions.Regex.Split(message2, "\b(\w+)(\W){1,2}"))

    For i As Integer = 0 To stringCollectionmessage1.Count - 1

        If Not stringCollectionmessage1.Contains(stringCollectionmessage2(i)) Then
            lblMessage.Text += "<font color='Red'>" & stringCollectionmessage2(i).ToString() & "</font>" & " "
        Else
            lblMessage.Text += stringCollectionmessage1(i).ToString() & " "
        End If
    Next
End Sub

Output

Mr Dhinna ' s broad international experience provides the board of directors with his unique insights related to Blockbuster strategy operations and businessas a global company Mr Dhinna brings to the board significant commercials transaction less from his Kissinger Associates role till 25 / 06 / 2016 2018 well as domestic andinternational public policy experience Mr Dhinna has extensive knowledge in a number of important areas including innovative problem - solving related could not be opportunities particularly with regard to China and Japan He is also ex CFO of ABC Inc .