[02/03] how to send an empty text box value to database

i've created a web page taking inputs from user. There are some options for users which are optional. but when it is left empty; an error comes saying format of string is not correct. how can i do this? I've put "fieldvalidator" only for compulsory input. I'm inserting data in sql server 2000. here is my code

VB Code:

Sub SaveCustomer(ByVal s As Object, ByVal e As EventArgs) Handles btnSave.Click
 
        If Page.IsValid Then
 
            Dim objCustomer As New BusinessLogicLayer.MyCustomers
 
             objCustomer.RecordId = CType(txtRecordId.Text, Long)
            objCustomer.CustomerNo = CType(txtCustomerNo.Text, Long)
            objCustomer.RecordDate = CType(CurrentDate.Text, DateTime)
            objCustomer.Customername = txtCustomerName.Text
            objCustomer.CustomerCompanyName = txtCompanyName.Text
            objCustomer.CustomerBillingAddress = txtBillingAddress.Text
            objCustomer.CustomerTelePhoneNo = CType(txtTelePh.Text, Long)
          
 
           If Not objCustomer.Save() Then
              lblError.Text = "Could not save Customer"
 
           End If
        End If
    End Sub 'SaveUser

while i've declared variables in "MyCustomers" class as. here i've initialized those variables which are optional

VB Code:

Private _CustomerNo As Long = 0
        Private _RecordId As Long
        Private _RecDate As DateTime
 
        Private _Customername As String
        Private _CustomerCompanyName As String = ""
        Private _CustomerBillingAddress As String
        Private _CustomerTelePhoneNo As Long

1) use integer instead of long.
2) what field are NOT required.
3) When u get the error, which line is it on, and what is the value in the textbox?

Woka

Quote:

---

Originally Posted by Wokawidget

1) use integer instead of long.
2) what field are NOT required.
3) When u get the error, which line is it on, and what is the value in the textbox?

Woka

---

1. I can't use integer cuz digits required to enter may lie in between 10-15
2. All of the fileds which i have initialized here are not required.
3. it's giving error on customerNo

VB Code:

objCustomer.CustomerNo = CType(txtCustomerNo.Text, Long)

10 and 15...???

ie 10,11,12,13,14 or 15???

so, when it fails, what is txtCustomerNo.Text? is it "" by any chance?

Woka

Quote:

---

Originally Posted by Wokawidget

10 and 15...???

ie 10,11,12,13,14 or 15???

so, when it fails, what is txtCustomerNo.Text? is it "" by any chance?

Woka

---

:D well; it's 13

how can it be ""?? i've pasted code. i'm converting it to long before setting the value. in MyCustomer class; i've initialized it as '0'. then how can it be "" is user doesn't enter anything in it. i mean leave it empty :confused:

well if the number is less that 32000000 ( or something like that, can't remember the exact max value for an int, but .net int is same as vb6 long) then use an int, not a long.

also:

if the textbox contains "" and you do:

VB Code:

CType(txtCustomerNo.Text, Long)

Then u will get an error as "" cannot be converted to a number.


Woka

Quote:

---

Originally Posted by Wokawidget

well if the number is less that 32000000 ( or something like that, can't remember the exact max value for an int, but .net int is same as vb6 long) then use an int, not a long.

also:

if the textbox contains "" and you do:

VB Code:

CType(txtCustomerNo.Text, Long)

Then u will get an error as "" cannot be converted to a number.


Woka

---

I get an error saying
"Input string was not in a correct format"
then what should i do?? In database i've declared it as BigInt cuz only "int" doesn't store value of more than 10 digits. we see in filling the forms of web service that it allows some filed to be optional. say when filling forms for email addresses. there are many optional fields. how they do this?? plz help me. it's urgent!!!!

are you storing a number, or text...ie:

"64343539836373" is not always a number if you catch by drift...ie...if your storing an order number. lets say in the format Year, month, day:

20060723

This is not a "number", but instead a unique code, and should be stored as text in the DB.

Write a function like:

VB Code:

Public Function ConvertToInt(Byval TextValue As String) As Integer
   Dim IntValue As Integer = 0
   Try
       IntValue = System.Convert.ToInt32(TextValue)
   Catch ex As Exception
       'error, cannot be converted
   End Try
 
   Return IntValue
End Function

Then do:

VB Code:

MyCustomer.CustomerID = ConvertToInt(txtID.Text)

or something like that.

woka

While using the exception approach will work, it is catching the error after it occurs.

Which is not as effecient as preventing it in the first case.

Why not just use an if statement to see if there is a value in the box before converting?