Checking for existing date record failing

Question

I am using a function which is to pass in a string DateTime to a SQL Command and return if there are records or not.  The date string which I pass in is formatted like this: "05-Sep-18, 16:24:58".  The table in SQL which I am selecting the data from has the field set as a DateTime field. The code I am using is as follows:

 Public Function SqlExists() As Boolean
        ' What if that records already exists in the database?

        Dim recFile As String = ProcessFiles.HeaderTable.Rows(7).Item("Values")
        Dim cleaned As String = recFile.Replace(",", " ")
        Dim tmpDate As DateTime = DateTime.Parse(cleaned)

        'Dim recFile As String = dataFile
        If recFile <> Nothing Then
            Dim builder1 As New SqlConnectionStringBuilder(ConnectionString)
            builder1.InitialCatalog = "ctc_custom"
            Dim cn As New SqlConnection(builder1.ConnectionString)

            ' Need to build the TestID as a unique value and save it somehow
            Try

                cn.Open()
                Using cmd As New SqlCommand("SELECT * FROM [ctc_custom].[dbo].[HPLC_Params] WHERE [Injection Date] = @recFile", cn) With {.CommandType = CommandType.Text}

                    cmd.Parameters.AddWithValue("@recFile", tmpDate)

                    Try
                        Using reader As SqlDataReader = cmd.ExecuteReader()
                            If reader.HasRows Then
                                ' Record exists do not add
                                Return True
                            Else
                                Return False
                            End If
                        End Using
                    Catch ex As Exception
                        ErrorLogger.WriteToErrorLog("Errors", ex.Message, ex.StackTrace)
                    End Try
                End Using
                cn.Close()
            Catch ex As Exception
                ErrorLogger.WriteToErrorLog("Errors", ex.Message, ex.StackTrace)
            End Try
        End If
    End Function

I am wondering if this code will work properly or do you see any issues with it where it would always return a True value?  I can get the validation to work 3 times in a row and then it returns true always.  Please suggest better ways to do this validation.

Answer 1

If the field [Injection Date] is a DateTime field in SQL-Server and culture is EN I'm surprised it even works. The conversion should fail.

While this would be fine which excludes the comma.

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Answer 2

When I run the application the value which tmpDate receives is #7/26/2018 02:57:13 AM  if the passed in date is "26-Jul-18, 2:57:13"

So technically all I would need to do is use the value that the cleaned variable returns rather than the value which tmpDate returns and it should work?