Assume we have a form that will accept two data values via t

Assume we have a form that will accept two data values via textboxes - a string of text (the textbox, is named txtString) and a value to be searched for (txtTarget). It also has a button (named btnSeek) that will hold the code we write here. The goal is to display the starting location of the first occurrence of the target value in the string using a massage box. Provide AB statements to determine the value sought and display it via a message box. Show any variable declarations (if you Use variables, declare them).

Solution

Sub btnSeek_Click()

Dim Index As Integer = txtString.IndexOf(txtTarget)

return Index

End Sub

The above given sub function will do the required task. And here it uses the builtin function IndexOf() to find the first occurence of the substring in the given string and returns the position if any occurence is present.

public Function Find() As Integer

Sub btnSeek_Click()

Dim length As Integer = txtTarget.Length

Dim found As Integer =-1

For iPosition As Integer =0 to len(txtString)

If txtString.SubString(iPosition,length) = txtTarget Then

Return iPosition

End If

Next iPosition

Return -1

End Sub

End Function

These VB statements are used to identify the first occurence of substring in the given string