VB - Create The Simplest Partial Class In Order To Access A Table Property
Nov 23, 2010I'm stuck when trying to create the simplest partial class in order to access a table property. I have a LINQ auto generated DataContext with:
[Code]...
I'm stuck when trying to create the simplest partial class in order to access a table property. I have a LINQ auto generated DataContext with:
[Code]...
I have extended an Entity Framework 4 entity class with a calculated property in a partial class. This member is not available on the client to which the entities are exposed via WCF RIA Services.when using C# appears to be changing the extension of the partial class file from .cs to .shared.cs. I tried this with my VB.Net solution (.vb to .shared.vb) and got a long list of errors. I believe what happened is that the partial class lost its association with the entity on the client - it inherited from object rather than EntityObject.
My best guess is that this is related to the way that VB.Net handles namespaces.Each project has a 'Root Namespace' which is prepended to anything that is defined within a code file. C# has a 'Default Namespace'which is the namespace into which new types are placed by default - via a namespace statement within the file.The partial class is probably having the client namespace prepended to it which puts it into a different namespace than the entity with which it is associated on the server.Is there any means of extending an entity in such a way that those extensions are available on the client via WCF RIA Services and VB.Net?
I am using Linq to Sql that generated a data contract for a table. I have a date field in that table which is a non-nullable field. I need to override the auto generated property of the date field to return a specific value, something like [code]Is it possible to override an autogenerated property in the designer.vb file using a partial class? I dont want to create a new property as it is currently being accessed in n number of places and I dont want to change it in every place.
View 1 RepliesI have a class that add extra information about a column for linq2sql (see code below) right now, I have to explicitly tell what column I want that info on, how would you put that code with a loop on every column in every table from a dbml file? I was doing my test on a very very small DB, now I have to implement it on a much more bigger database and I really don't want to do it manually for every tables/columns it will take hours.
how it's being used:
Partial Class Contact ''contact is a table inside a dbml file.
Private _ContactIDColumn As ExtraColumnInfo
Private _ContactNameColumn As ExtraColumnInfo
Private _ContactEmailColumn As ExtraColumnInfo
[Code]....
I have procedure (Import) that calls a for a new instance of frmImportData. I also have a class name clsBatch that has a data table property called prpParametersTable.For some reason, I get an error (indicated below with ERROR>>>) when trying to assign prpParameterTable to cv_dtImport2. The error states "Object reference not set to an instance of an object.". Why does this error not happen when I assign dtBP to cv_dtImport1? Both cv_dtImport1 and cv_dtImport2 are equal to Nothing and in my Import procedure dtBP = prpParametersTable.
Public Sub Import(ByVal clsB As clsBatch)
Try
Me.cv_clsB = clsB
[code]....
This is a bit of a continuation from a previous post for which AtmaWeapon was very informative.
Problem:
A parent class has a sub class with various properties. A property of the parent class is a List(of T) with T = the sub class The issue is how to store data in the sub class of the instantiated parent
Some example code (hopefully formatted correctly):
Code:
'=========== Class Definitions =============
Public Class courseClass
Public Class timeTableClass
[Code].....
Private _Order As Order() Public Property Order() As Order() Get Return _Order End Get Set(ByVal value As Order()) _Order = value End Set End Property
I need to get property name 'color' inside the 'order()' array, i am trying ' Order.color ' but its not getting,
When you create a property in a VB.NET class how do you tell it which category it will belong to when it shows up in the property window?
View 4 RepliesI have a function that updates a Client in the database. A client object is passed in, along with a string array of fields/properties that should be updated. I need a way of accessing each property in the client object, based on what is in the array. Basically, I am looking for the VB .NET equivalent to this javascript:
var fields = ["Firstname","Lastname","DOB"];
for(field in fields)
{
[code]....
Is there a (simple) way to connect a textbox, label etc. to a property in a class?I have a project with a complex series of dialogs to enter data into a list of a costum class describing an experiment with many parameters that are stored as properties (both simple variables such as strings and integers, but also more complex ones).I need both to be able to update the list of my experiment class, but also to go the other way to populate the dialogs from the class.It can of course be done outside the class and the dialogs in separate subroutines. This however, quicly becomes unmanagable and hard to maintain as the dialogs and experiment class is expanded with new elements.If there was a simple way to connect say a textbox or label in a dialog with the appropriate property holding the information it would make it much easier.
View 5 RepliesI'm having a few problems converting some code into VB.NET from C#. Most of the translating is done, but I am getting errors when I try to run my code, and I can't figure out what is causing them. Here is the Sub I translated.
Public Sub CreateWidget()
Dim blue As LCDColor
blue.Red = 0
blue.Green = 0
[code]....
The error I receive on this line ("vision.Widgets.CreateWidget(wg1)") reads "In order to evaluate an indexed property, the property must be qualified and the arguments must be explicitly supplied by the user."
I receive a System.Data.SqlClient.SqlException in the following code: Specifically Incorrect syntax near ' In order to evaluate an indexed property, the property must be qualified and the arguments must be explicitly supplied by the user. The exception detail in its entirety is shown below the code.
[Code]...
Interface makes sure a class does have a Method / Property, However is there a way to create an unInterface, making sure that the class does not have a method / property or is there a way to implement something that will unimplement every other implements except for itself?
what i want to do: i've got a class that serves as a storage for information only, so i decided to give it a blank interface IBank, the other classes that share this feature will implement this interface. they should not implement any other interface the use is that when i seek out the interface of a class and realise that its IBank i know that its just a class for info storage.
I have:
Page.aspx
Page.aspx.vb
TestClass.vb
I'm trying to access a shared property of the TestClass class from the Page.aspx.This code works fine:
<head>
<script language="JavaScript">
<% if System.Globalization.CultureInfo.CurrentCulture.Name.ToLower = "pt-br" Then %>[code]......
I can't seem to find the correct words to search for an answer. I'm using VS 2010 so I have auto-implemented properties.I have a class and I want to access the properties by a string.
Public Class MyClass
Property Prop1 As String
Property Prop2 As String[code].....
But, I also want to be able to access the variables something like this way....
Dim MyVar = New MyClass
MyVar.Items("Prop1") = "Prop1 Value"
MyVar.Items("Prop2") = "Prop2 Vaule"
How can I setup MyClass to work both ways?
In my never ending search for more knowledge, I have come across Partial Classes. I was wondering if some of the kind people who actually understand the uses could explain some of them to me. Now I know that when we create a form that we actually create a partial class which the generator rewrites when we add a control or change a property at design-time, and this allows us not to have to worry about setting up the controls ourselves.
[Code]...
I have a class that exposes an auto implemented property Enabled
[Code]...
But If I had not use an auto implemented property and declared my own backing-field as follows this is accessible from the subclass: Private _Enabled as Boolean ---- EDIT ----
The abve line is incorrect - this is not possible, it was in fact Protected in the original code which allowed access from the sub class See @JonSkeet answer ---- EDIT Of course I can just access Enabled from the sub class to work around this but can someone explain why this is the behaviour?
Is it possible to create a user control with a list of custom class type property? If it is, how can I? The issue is that, in designer mode the property is not displayed in property window. I can add the list on markup but when i switch to the designer mode it gives an error which is 'The user control does not have a public property named BookList'.
View 1 RepliesWhen you create a new asp.net page in VS 2008 and choose code behind, it also creates the typical aspx.vb or aspx.cs file to go along with it.
At the top of those files, VS names the 'Partial Class' name the file structure and/or name of the aspx file.
The question: Is there a best practice for this? Can I just use a single class name for all the pages in my application or perhaps a single directory instead of having to give each one a unique name?
I would like to create a partial class for my form. I have a lot of events, and it gets messy, so I would like to break up sections into their own files. The problem: When I create a partial class of my form, say:
Partial Public Class Form1
End Class
Visual Studio decides I need another form for this partial class.
1. How do I create a partial class for a form?
2. If I cant do that, how can I break up all the events in my form into different files?
How do I insert the partial class to be correct?
Imports System.Data
Imports System.Data.SqlClient
Partial Class
[code]....
I am reading a book (ASP.NET 3.5 Enterprise Application Development with Visual Studio 2008: Problem Design Solution, WROX)The source code is written in C#, but I am a VB guy, so I am giving it a try. Somewhere in the 2nd chapter, there is a Linq to Sql file used that is generated by drag&dropping the DB tables from the Database Explorer. Because some tables have the same type of fields, there is an interface generated called IENTBaseEntity. The writer says its a good practice to implement this interface in another partial class (not the designer.vb file!). The reason for this is that when the LinqToSql file is modified (and regenerated) the changes wont be lost.
In C# this solution is easy to do (i think), but in VB.Net I get an error, because the concerning properties in the LinqToSql file do not append the 'Implement IENTBaseEntity.Property' line. When I press [Enter] after the interface implementation line, VS generates other properties like this
Partial Public Class ENTUserAccount
Implements IENTBaseEntity '--->This line results in the error
' This is not the way it should be
Public Property InsertDate1() As Date Implements IENTBaseEntity.InsertDate
Get
End Get
[code]....
I'm having some trouble with a class that uses the ToolStripControlHost, I have to create a label and a label beside the textbox, this works, the problem now and I can not access the property. Text of textbox (txt). the class to this:
Public Class ToolStripTextBoxWithLabel
Inherits ToolStripControlHost
Public Event TextoAlterado(ByVal sender As System.Object, ByVal e As System.EventArgs)[code]......
code for creating a class in vb.net for a database table that includes insert,delete,update function.
View 1 RepliesI have a SQL 2005 table called Customers and i would like to query the table for exact match and partial match. The exact match query is working OK but when i use the partial match, it doesnt return any result. Strange thing is, it works inside the query designer, it returns rows. On the dataset, if i right click and say 'Preview Data' and supply the search criteria, it doesnt bring in any rows. Same happens in the vb.net form also. Instead of partial string, if i supply the full customerid, it returns a row.Whereas I can return rows on another table, Suppliers. I dont know where the problem lies. Here is the sql:[code]In fact, I am trying to use the wizard generated code and details on the form. No changes done to the code or form.The customer id is nchar(10) column and is the primary key also. I ran the same steps on the Northwind database too, and the same problem exists.
View 4 RepliesThis might not be so 'VB' as it is 'SQL using VB' I have an application with a built in MS Access DB. I have a table that has a column full of integers, I shoot the DB a SQL "order by 'column name' " string and it returns the table ordered by my column of integers.BUT it returns them like this, and I want them like this
0 6
1 5
2 4
[code]....
How do I get the OrderBY to do a descending list starting with the highest number?
I am currently working on a project of "interpreting" C# into VB. The project involves adding images to a database, retrieving images from the database and presenting them in thumbnails. Right now I have the following Public Class with the Variable that needs to be assigned:
VB:
Imports System.Data
Imports System.Drawing
Imports System.IO
[code]....
I have a textbox which is bounded to the typed dataset. If the user in the textbox &hit keydown, it should allow only numeric values with 2 decimal points and also it should not allow more than one "."(dot). I found many but all thats are using textbox event
View 2 RepliesI am testing custom data validation with partial classes. It is a Windows Form Entity Framework application .In the partial class file (time.vb) the code is:[code]What is wrong with my code? How can I handle the exception message in the main form (thrwon by the OnDataFundChanging event)?
View 3 RepliesI am trying to write some unit tests on a class that looks like this, using Moq [code] the parameterized constructor is private or internal one of the two methods relies on the result of the other.I want to check that when GetThisOrThat is called with a value, it actually calls GetThis. But I also want to mock GetThis so that it returns a specific well-known value.To me this is an example of Partial Mocking, where we create a Mock based on a class, passing the parameters for the constructor. The problem here is that there is no public constructor, and therefore, Moq can not call it..I tried using the Accessors generated by Visual Studio for MSTest, and use those accessors for the mocking, and this is what I came up with [code]
View 1 Replies