Removing unnecessary 0's from an array? " InvalidCastException was unhandled"

[rosleenXOXO]

Public Class Form1

Dim Array(24) As Integer
Dim J As Integer = 0
Dim MyArray As New List(Of Integer)


Private Sub btnPutNumberIntoMyArray_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnPutNumberIntoArray.Click
Dim number As Integer
Integer.TryParse(txtNumbers.Text, number)
MyArray.Add(number)

txtNumbers.Clear()
txtNumbers.Focus()

End Sub

Private Sub btnDisplayNumbersInMyArray_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDisplayNumbersInArray.Click
txtDisplayNumbers.Clear()
txtDisplayNumbers.Focus()

For J As Integer = 0 To MyArray.Count - 1
txtDisplayNumbers.Text &= MyArray(J).ToString & Environment.NewLine
Next

End Sub



Private Sub btnDisplayLargestNumber_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDisplayLargestNumber.Click

Dim Largest As Integer
Largest = MyArray(0)
For J = 1 To 24
[B]If MyArray(J) > Largest Then[/B]
Largest = MyArray(J)
End If
Next
txtDisplayNumbers.Text = CStr(Largest)

End Sub

Private Sub btnDisplaySmallestNumber_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDisplaySmallestNumber.Click

Dim Smallest As Integer
Smallest = MyArray(0)
For J = 1 To 24
If MyArray(J) < Smallest Then
Smallest = MyArray(J)
End If
Next
txtDisplayNumbers.Text = CStr(Smallest)

End Sub
Private Sub btnDisplayRange_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDisplayRange.Click

Dim Smallest As Integer
Dim Largest As Integer
Smallest = MyArray(0)
Largest = MyArray(0)
For J = 1 To 24
If MyArray(J) < Smallest Then
Smallest = MyArray(J)
ElseIf MyArray(J) > Largest Then
Largest = MyArray(J)
End If
Next
txtDisplayNumbers.Text = _
CStr(Smallest) & " to " & CStr(Largest)

End Sub
Private Sub btnDisplaySumOfNumbers_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDisplaySumOfNumbers.Click

Dim Sum As Integer
For J = 0 To 24
Sum = Sum + MyArray(J)
Next
txtDisplayNumbers.Text = CStr(Sum)

End Sub


Private Sub btnDisplayMean_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDisplayMean.Click
Dim lCounter As Long
Dim dTotal As Double
Dim dAverage As Double

dTotal = 0
For lCounter = 0 To UBound(Array)
dTotal = dTotal + MyArray(CInt(lCounter))
Next
dAverage = dTotal / (UBound(Array) + 1)
txtDisplayNumbers.Text = CStr(dAverage)
End Sub
End Class

This is my full code, could you please tell me what i am doing wrong?