Is there an easier way to prevent a duplicate insert after refresh? The way I do it now is to select everything with the all fields except ID as parameters; if a record exists i don't insert. Is there a way to possible detect refresh?
I have a form where two fields on the first page of the form make up the primary key. I want to check for duplicate values before attempting to insert the record, since I don't want the user to go all the way through the form only to find out they can't submit it. So I'm trying to check for duplicate values when the user tries to go to the next page of the form. I wasn't quite sure how to do it, and sure enough I'm getting an error. ("Object reference not set to an instance of an object.") The problem is apparently in my if statement, "If myValue.Length > 0 Then", but I'm not sure what needs to be in place of that.
Protected Sub CustomValidator1_ServerValidate(ByVal source As Object, ByVal args As System.Web.UI.WebControls.ServerValidateEventArgs) Handles CustomValidator1.ServerValidate 'get values
I have two table, src_table and dest_table src_table contain multiple rows including duplicates I want to copy rows from src_table to dest_table without duplicates.
Is there any reason to favor one of these approaches over the other when inserting into a generic dictionary with the possibility of a key conflict? I'm building an in-memory version of a static collection so in the case of a conflict it doesn't matter whether the old or new value is used.
If Not mySettings.ContainsKey(key) Then mySettings.Add(key, Value) End If
I'm trying to populate the list of a combobox by binding it to a datatable. Also, I want the selected value of the combobox to be bound to an object property so that when the selected value changes, it's automatically updating the object. However it's causing an error at runtime: "This causes two bindings in the collection to bind to the same property.
Parameter name: binding" I thought binding the dropdown list to a datatable and the selected value to an object were different properties but obviously I'm not getting it right.
Code:
Private Sub PopulateSiteSelect() With Me.PlanSiteSelect If _Plan.PlanID <> Nothing And _User.UserID <> Nothing And _Plan.Category <> Nothing Then
I have this data in txt file and the data keeps changing all the time.
[code]...
I would like to read all lines and compare, if the same name and same address is found, which is in the [......], then i need to count it and show the most frequent buyer!should i read it all and put in array, and compare and put the duplicate data and count into another array?
My Task Background :I have list of data items and have to calculate/aggregate details about each data item and populate that to SQLServer database.I can do 1 by 1 insert [Traditional method]But, the application needs to perform good.Is it possible to aggregate the data in a 2d array and dump into database @ once ?' Populate this and insert it to database.
Private data(100, 100) As Object
So, how to do that ?Also, is it possible to use dataset in some way ?
i was coding vb6 since 4 years.and few month ago i decided to learn Vb.net and i'am working with VS08I'm would use this Socket class HereBy jmcilhinneyBut i need to replace ComboBox by a ListView and i don't really know how to do that because the both don't work
I am writing a program with VB.NET, there I have to select data from one table. Then I have to update about 4 tables and insert to 2 Tables. Which approach will be ok for me? I'm thinking to use DataSet.
I am having problems with my code, where I get the "Object cannot be cast from DBNull to other types" message when Insert(). I get the message on every Insert to this table, even though the data is successfully inserted. If I Update the same data after Insert(), it does so without error. I have checked my values and none of them are DBNull. Even when the same values are passed on Insert that are passed on Update.
My code is : Private Sub Save() Dim bo As tbl_GL bo = New tbl_GL() bo.ConnectionString = AppConfig.ConnectString [Code] .....
I am trying to pass a list in string.format as the parameters to the SQL statement, but I get the following error: Index (zero based) must be greater than or equal to zero and less than the size of the argument list. I know that I can get it to work when I list out each individual list member as the arguments, but I am wondering if there is a shortcut so I can just use the list object as the only argument.
I am looking for a vb.net library where I can insert data into an object and have it spit out a json formatted string, and also take the string in again to rebuild the object.I am not that concerned with mapping it to preexisting objects.I have searched around and every single library I've found either can't read the strings in again, interprets them as one long string instead of breaking them up into parts, or fails to work entirely (asp.net can't even find any public members).
I am trying to save a new object to the database using petapoco.I have an object that uses a Guid for the primary key.Here is an example of the objects primary key property.
<PetaPoco.Column()> _ Public ReadOnly Property Primkey() As Guid Implements IStandardDocument.Primkey Get
The sql that is generated is an update with a primkey of 00000000-0000-0000-0000-000000000000 instead of an insert. So new records are never inserted.If I have an existing object with a valid guid the update and delete all work correctly.
I want to insert a Windows Media Player object in my Form, but I have not the control on my Toolbox.
I have done the steps:
Right-click the Toolbox -> Choose item -> COM Components -> add Windows Media Player component (which references to C:WindowsSystem32wmp.dll)
But there is not the control on my Toolbox.
In my project references I see "MediaPlayer" into "Imported namespaces" and it is checked. In the references window it is also present "Windows Media Player". Where is the error?
I have a List object and I want to remove the duplicated items but leaving at least one of the duplicated items in the list;I wrote something like this however I would optimize this code for better performance, is there something faster?
Const chars As String = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz" Dim rnd As New Random() Dim mylist As List(Of String) = Enumerable.Range(1, 100).Select(Function(i)
I am somewhat new to object oriented programming and am attempting to flatten a Linq object hierarchy by using a shim class.how to initalize a derived class with property values from a base class?I have two objects, a base object with about 100 properties, and a derived object which inherits from the base object and adds a few additional properties beyond those of the base object. My simple constructor creates the derived object, but I am looking for a way to initialize the derived object properties with values from the base object.Right now I am using reflection to iterate over the properties individually and I suspect there may be a better way. The following example shows my shim class constructor for the derived class, and two properties:
newProperty1 - a new string property of the derived class
flattenedProperty2 - a new string property of the derived class, copied from a 2nd-level object of the base class
Code example:
Public Class derivedObj Inherits baseObj Private _newProperty1 As String[code].......
Is this the correct constructor approach to flatten the object hierarchy using a shim class? My second question relates to initialization of properties in the derived class. The constructor above creates the derived object, but what is the best way to initialize the derived object properties with values from the base object? The following code uses reflection to iterate over the properties individually, but I suspect there may be a better way.
Code example:
' property names are in the string array fieldNames
'baseObjQuery is an ienumerable of baseObj
'derivedObjList is a list of derivedObj[code].....
Is there a simple way to initialize values for the properties in the derived object based upon the values of the common properties in the base object?
im trying to write to an sql database. im inserting an image, as well as some other information. I am using the following code which works fine, as long as i do not add an extra column/variable "LOCATION" in to the mix and leave "
commented out. *this is undesireable as im trying to add extra criteria to be saved like LOCATION.
Try Dim st As New FileStream("\serverfolder1storage" & "pdftemplate.jpg", FileMode.Open, FileAccess.Read) Dim mbr As BinaryReader = New BinaryReader(st) Dim buffer(st.Length) As Byte
[code]....
i am trying to store the location e.g "c:file1.jpg" in the sql db. Can anyone reccomend a solution to this using OLEDB? ideally i need to add approx 4 more variables. e,g
Im getting an error with my insert statment "Syntax Error in INSERT INTO statement". I do not understand why. Im using global variables from form 1 and using them in form2 and trying to insert them from form2 into the database.
could someone tell me what i am doing wrong in this codeProtected Sub insert_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Insert.Click
Visual Studio 2008VB.NETFramework 3.5Windows Application
I have a SQL database names TestSQLVB
In it a table called tblTest2, with a three fieldstest2id , int, pk, increment by 1field1, varchar(50)field2, varchar(50)
I have a dataset named Dataset2.xsd
A tableadapter named tblTest2TableAdapter
A insert query names InsertTest2 with fields @f1, @f2 and ExecuteMode = Scalar
When I run the following code per MSDN [URL] the database does not get updated.
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim testds As New DataSet2TableAdapters.tbltest2TableAdaptertestds.InsertTest2("One", "Dog") End Sub
im in the middle of doing sql queries i can search my data base usingGetDateFrom (Select, from, where) Me.nameTableAdapter.FillBy(namenDataSet.descip, Me.box1TextBox.Text,Me.box1TextBox.Text, Me.box2TextBox.Text, Me.box2TextBox.Text)i have this working fine im struggling with inderting data to my databse i have made the query ..