How to allow null value inside datetime

Question

User66371569 posted

I have textbox     for date 

I am using this DateTime.ParseExact(Startdate.Text, "dd/MM/yyyy", CultureInfo.InvariantCulture)  to  insert date   its works  fine  but sometimes I need to insert null or empty

I got error  

how can I solve tis

Answer 1

User-1716253493 posted

If empty pass dbnull.value

Answer 2

User66371569 posted
I am using this code inside insert method

Insert into table (startdate) values (DateTime.ParseExact(Startdate.Text, "dd/MM/yyyy", CultureInfo.InvariantCulture))


how to apply null value in above code

Answer 3

User-1716253493 posted

Use parameterize query

Insert into table (startdate) values (@startdate)

you can pass dbnull.value when textbox text is empty

or change the query

Insert into table (startdate) values (null)

Answer 4

User66371569 posted
u mean like that

Dim sdate as string= startdate.text
If sdate=' ' then
 dbnull.value
Else
Dim Ddate as Datetime=DateTime.ParseExact(sdate, "dd/MM/yyyy", CultureInfo.InvariantCulture)

insert into table startdate values (sdate)

Answer 5

User-1716253493 posted

        cmd.CommandText = "Insert into table (startdate) values (@startdate)"
        If sdate = Nothing Then
            cmd.Parameters.AddWithValue("@startdate", DBNull.Value)
        Else
            cmd.Parameters.AddWithValue("@startdate", DateTime.ParseExact(sdate, "dd/MM/yyyy", CultureInfo.InvariantCulture))
        End If

Answer 6

User66371569 posted

Dim ds1 As New SqlClient.SqlCommand
'Dim intcount1 As String
Dim str As String

conTest.Open()

str = " insert into HpdCoboneRequests (cobonerequestid,coboneno,StartDate,Enddate,coboneid,operationid) values('" & cobrequest.Text & "',N'" & cobno.Text & "','" & "@startdate" & "','" & "@startdate" & "',N'" & cobid.SelectedValue.ToString & "',N'" & Session("op").ToString & "')"

Dim ds As New SqlClient.SqlCommand(str, conTest)
Dim s As Integer

Dim sdate As String = Startdate.Text
If sdate = Nothing Then
ds.Parameters.AddWithValue("@startdate", DBNull.Value)
Else
ds.Parameters.AddWithValue("@startdate", DateTime.ParseExact(sdate, "dd/MM/yyyy", CultureInfo.InvariantCulture))
End If

s = ds.ExecuteNonQuery()

when run code   and insert null value  or also  right date       both occurs error "Conversion failed when converting date and/or time from character string" 

Answer 7

User66371569 posted
thank u so much It worked