The Contains method in the VB.NET String Class check the specified parameter String exist in the String

System.String.Contains(String str) As Boolean

Parameters:

String str - input String for search

Returns:

Boolean - Yes/No

If the str Contains in the String then it returns true

If the str does not Contains in the String it returns False

For ex: "This is a Test".Contains("is") return True

"This is a Test".Contains("yes") return False

Exceptions:

System.ArgumentNullException : If the argument is null

Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles Button1.Click
        Dim str As String
        str = "VB.NET TOP 10 BOOKS"
        If str.Contains("TOP") = True Then
            MsgBox("The string Contains() 'TOP' ")
        Else
            MsgBox("The String does not Contains() 'TOP'")
        End If
    End Sub
End Class