How can I check whether the data already exists in combobox list?

How can I check if the data from cmbTypeYacht.text already exists in cmbTypeYacht.list?

Here's what I've got:

Dim TypeYacht As String 'Type of yacht input

TypeYacht = cmbTypeYacht.Text

If TypeYacht = ("cmbTypeYacht list") Then
    MsgBox "Type of Yacht is already on the list", vbExclamation, "Yacht Chantering"
Else
    cmbTypeYacht.AddItem cmbTypeYacht.Text

    With cmbTypeYacht
        .Text = ""
        .SetFocus
    End With
End If

sorry about the tag im not quite sure which is it but im using Microsoft Visual Basic app.

The ComboBox class has a FindStringExact() method that will do the trick for you, like this:

Dim resultIndex As Integer = -1

resultIndex = cmbTypeYacht.FindStringExact(cmbTypeYacht.Text)

If resultIndex > -1 Then
    ' Found text, do something here
    MessageBox.Show("Found It")
Else
    ' Did not find text, do something here
    MessageBox.Show("Did Not Find It")
End If

You can also just loop through the list as well, like this:

Dim i As Integer = 0
For i = 0 To cmbTypeYacht.Items.Count - 1
    If cmbTypeYacht.Items.Contains(cmbTypeYacht.Text) Then
        MessageBox.Show("Found It")
        Exit For
    End If
Next