vb net tutorial

code is as follows:Now let's look at the results of the operation:Allowusertoaddrow The following error occurs when this property is changed to true:Because the value of the cell is empty, a control is performed. The System.NullReferenceException exception occurs when the ToString () operation. For this I will remove the ToString, will not error, in addition you can be the value of the advanced line is empty to judge if not empty, in the ToString () operation, the above is in the code to modify

VB. NET of form1.vb Code : Private Sub button#click () SubButton#click (ByvalSenderAsObject,ByvalEAsSystem. eventargs)HandlesButton1.clickForm2.instance (Me)Form2.showdialog ()End sub The VB. NET code of form2.vb: Priva

I prefer to use C #, but VB and VB. NET are also very desirable. Making full use of these functions can get twice the result with half the effort. Some of the original function libraries in VB are in Microsoft. VisualBasic. interaction, such as inputbox and msgbox. If you use inputbox in C #, You can implement it you

Go to C #. Net to call the DLL compiled by VB. Code The example (I made some changes) is transferred from: how to call the DLL written in VB6 in http://www.taotechinfo.com/collect/2010222/n68565463.html. net. Take C # as an example. Hope to help people who encounter problems. This example is divided into two parts. First, generate the DLL of

With Microsoft. the launch of the NET development platform has undoubtedly brought great news to countless VB developers, including no inheritance, ugly error capturing, no object pool, and no underlying development, it is followed by a complete OO-oriented feature, a wide range of class libraries that support XML. When someone prefers C #, C ++ developers are dismissive about it, but what is more important

VB. NET sets the display level of controls and forms. vb.net controls Preface: When VB. NET is used to develop the RF Detection System ADS, when an existing target MDI subform is activated, it is overwritten by other subforms, so that the target MDI subform cannot be displayed. How can this problem be solved? I saw a p

Notes | concepts | Grammar begins with basic concepts and grammar Learning a language, especially now is the development of visualization, but I suggest that it is not urgent to drag a few controls first, but the sense of the first to understand the concept of the language, grammar and norms. Vb. NET is very close to the previous VB6, but since the vb.net is a new object-oriented language, there are som

Vb. NET Audio playback Montaque (original) After the VB6 upgrade to. NET, some people are not clear about the sound processing, such as when the program is wrong, customizing a sound playback, or the program's background music, including game music, and so on. Here are some simple and achievable solutions in vb.net: 1. Beep The simplest method is to make a sou

ASP. NET (VB) adds watermark text to the image: Specifies the image to add watermark text DimimgAsImage = Image. FromFile (Server. MapPath ("~ /Upload/1.jpg")) 'Create a bitmap object for drawing operations. You cannot directly operate on a format other than BMP, maybe) DimbitmapAsNewBitmap (343,498) 'Specifies the font of the text to be drawn. DimfAsNewFont ("", 16, FontStyle. Underline) 'Te

1. How to drag a form without borders? This function can be implemented in VB6 only by using API functions. In VB. NET, You can implement it with your own functions. First, set the formborderstyle attribute of the form to none to remove the border of the form, and then add a button on the form. The code in the form is as follows:Code: Public class form1 Inherits system. Windows. Forms. Form Private mo

This article mainly introduces how to use MySQL in VB. NET applications. The operation is based on Visual Studio IDE. if you need it, refer Xuyan Using the wizard to connect to the MySQL database in Visual Studio is quite tricky. Because MySQL is not supported by VS2012 by default (such as SQL Server ). This article describes how to use VB..

ArticleDirectory Core code: In the previous summary of C # (VB. NET) Operating Windows built-in firewall, we mentioned the following figure. In this article, we will implementEnable/CloseAndAllow exceptions?Functions First, because Windows comes with the "Security Center" Security Center FunctionProgramWhen the firewall is disabled, a prompt is displayed in the security center, T

VB. NET first edition of the computer room charge system, the completion of the acceptance of the time, the problem is also greatly exist, no use on the design mode, what triggers, stored procedures, are not used to see its small partners, seven layer implementation login? What is that, compared to my three floor, more than twice times plus one, by looking at the information, look at the blog, suppressed fo

Vb. NET date (time) formatting 5 ways to useThe following time takes September 26, 2009 as an example1th format: dd/mm/yyyy String.Format ("{0:dd/mm/yyyy}", DateTime.Now)o/p = 26/09/20092nd format: mm/dd/yyyyString.Format ("{0:mm/dd/yyyy}", DateTime.Now)o/p = 09/26/20093rd format: Dd/mm/yyString.Format ("{0:dd/mm/yy}", DateTime.Now)o/p = 26/09/094th format:String.Format ("{0:t}", DateTime.Now)o/p = 12:22 PM

, static members) Dim testscopefiled as New testscope Testscopesharedsubmethodone (testscopefiled) End Sub The ' Public Static function Testscopefunctiongmethodone () as String ' cannot declare a function method (or function functions) with Static, prompting an error: The method cannot be declared as " Static " The public Function Testscopefunctiongmethodone () as String ' cannot be accessed outside the class if it is changed to private Return String. Format ("Testscopefunctiongmethodone (): {0}

VB. Date-time conversion in net Just learn vb.net soon, in doing a few small examples when found often to the date time and the conversion between the string, now sorted as follows, if there is not the right place please point out. 1. Conversion between character type and date type The conversion of date type to character type is the simplest and can be directly converted. Dim dt as Date = NowDebug.WriteLi

,barr.length=36 Array.clear (Iarr, 0, Iarr.length-1) For I as Int32 = Iarr.getupperbound (0) to 0 Step-1 ' iarr.getupperbound (0) =5 ' The elements of the array are Iarr.setvalue (i, i) Next Array.Sort (Iarr) ' array elements sorted to 0,1,2,3,4,5 For i as Int32 = 0 to Iarr.getupperbound (0) ' Output array element Next ArrayList objects The capacity of the Ayyar is fixed, VB. NET