VB: checking textboxes if empty

halu again,

i have a problem dealing with my code. this i think is simple but i can't make it happen. i'm a newbie to this thing. hehe...

i'm trying to check an array of textboxes if one is empty. this is the flow.

textboxes are put to array, let's say:

Friend txt() As TextBox = {txtLastName, txtFirstName, txtMI, txtAddress, txtHomePhone, txtCellularPhone}

then i want to check if one of textboxes is empty. here is my code:

Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdd.Click
Dim i As Integer = 0
Try
While (i < txt.Length) And (Not txt(i).Text = String.Empty)
i += 1
End While
Catch ex As Exception
MsgBox(ex.Message)
End Try
If i < txt.Length Then
MsgBox("There's an empty textbox")
End If
End Sub

the problem is, it gets an exception with an error of:

Object reference not set to an instance of an object.

this is what i get when i try to click the add button...


need help,
ayan

i try this but to no success.

Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdd.Click
Dim txt() As TextBox = {txtLastName, txtFirstName, txtMI, txtAddress, txtHomePhone, txtCellularPhone}
Dim i As Integer = 0
Try
While i < txt.Length And (Not (txt(i).Text = String.Empty))
i = i + 1
End While
Catch ex As Exception
MsgBox(ex.Message)
End Try
If i < txt.Length Then
MsgBox("There's an empty textboxe(s)")
End If
End Sub

i think i can't make this code work.

it's just similar in other languages. the logic, you know. but this is not fair. huhuhuhu... i can't make it work.

i did a C code. check people. it works.

void main(){
char c[]={'a','b','c',' ','e','f'};
int i;

for(i=0;i<strlen(c)-1&&c[i]!=' ';i++);
if(i<strlen(c)) printf("there's a space\n");
}

by the way, the problem, in the above code (Visual Basic.NET) is an exception (again...)

it says about:

index was outside the bounds of the array

i think i can't make it. thanks anyway...

good luck to all


member,
ayan

halu,

i solved it. but the fact is i have a "not good idea". i hope this code helps to someone. this is the way i solved it.

Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdd.Click
Dim txt() As TextBox = {txtLastName, txtFirstName, txtMI, txtAddress, txtHomePhone, txtCellularPhone}
Dim i As Integer = 0
Dim flag As Integer = 0
While i < txt.Length And flag = 0
If txt(i).Text = String.Empty Then
flag = 1
End If
i += 1
End While
If flag Then
MsgBox("There is/are empty textbox(es).")
End If
End Sub

i set something like flag for a purpose of knowing if there's an empty textbox. thanx.

and oh, if anybody has some better ideas, can i have it? hehe... just a thought. but if so, thanx...

still needing help,
ayan

halu again,

i solved it. it just i encounter something in the net. check this site... www.programmersheaven.com

hehehe... i made a groupbox and check every control in the groupbox...

this is it.

Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdd.Click
Dim c As Control
For Each c In GroupBox1.Controls
If c.Text = String.Empty Then
MsgBox("Please Enter the " & c.Name, MsgBoxStyle.Information, "Note")
c.Focus()
Exit Sub
End If
Next
End Sub

thanx people... thanx for everything...

member,
ayan