This question already has an answer here: What is a NullReferenceException, and how do I fix it? 33 answers You need to create a new instance of the form you want to display. You do this by creating a variable of form T and then showing it. If you don't create an instance of your form the MainForm.Show() code will be invoking Show() on an null reference. If PasswordTextBox.Text = pas
这个问题在这里已经有了答案： 什么是NullReferenceException，以及如何解决它？ 33个答案 您需要创建要显示的表单的新实例。 你可以通过创建一个T形式的变量然后显示它来做到这一点。 如果您不创建窗体的实例， MainForm.Show()代码将在空引用上调用Show() 。 If PasswordTextBox.Text = pass Then Me.Hide() Dim theFormIWantToShow As New MainForm theFormIWantToShow.Show() End If
I'm having a lot of difficulty submitting a multi-part form through a VB.NET console application to BambooHR API. I've posted my current code as well as a sample request from the documentation below, when I run this code I get (400) Bad Request. I know the code is messy, but I've just been trying to get it to work. I was able to make a GET request work by using their sample code,
我在通过VB.NET控制台应用程序向BambooHR API提交多部分表单时遇到了很多困难。 我已经发布了我的当前代码以及下面的文档中的示例请求，当我运行此代码时，我得到（400）错误的请求。 我知道代码很混乱，但我一直试图让它工作。 我能够通过使用他们的示例代码来实现GET请求，但他们没有任何代码来执行此特定的API调用（上传员工文件）。 任何帮助，将不胜感激。 这是我的代码： Sub Main() upload(id, "https://api
I am making a chess game in vb 2010 here's my codes UPDATED Imports System.Drawing.Image Public Class Form1 Dim MD As Boolean Dim BLACK(5) As Image Dim WHITE(5) As Image Dim corX1st As String Dim corY1st As String Dim corX2nd As String Dim corY2nd As String Dim PIC As Image Dim box As PictureBox Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
我在vb 2010中制作了一个国际象棋游戏，这里是我的代码UPDATED Imports System.Drawing.Image Public Class Form1 Dim MD As Boolean Dim BLACK(5) As Image Dim WHITE(5) As Image Dim corX1st As String Dim corY1st As String Dim corX2nd As String Dim corY2nd As String Dim PIC As Image Dim box As PictureBox Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load BLACK
I have a problem with the auto-complete behaviour of comboboxes in VB.NET (with the .NET framework 2.0). I am using a combobox to type in numeric values, and its DropDown list to suggest possible numeric values. This list is sorted in ascending order, for example {"10","92", "9000", "9001"}. The combobox properties are set as follow: AutoCompleteMode
VB.NET中的组合框的自动完成行为存在问题（使用.NET Framework 2.0）。 我使用组合框键入数字值，并使用DropDown列表来建议可能的数值。 该列表按升序排序，例如{“10”，“92”，“9000”，“9001”}。 组合框属性设置如下： AutoCompleteMode：SuggestAppend AutoCompleteSource：ListItems DropDownStyle：DropDown 排序：错误 DropDown列表就是这样填充的： myCombobox.Items.Add（ “10”） myCombobox.Items.Add
I have an update function that updates an sql server db table through a dataset. One of the fields in the table is an integer and accepts null values. So when I am populating the update function I need a way to enter a null in when the function wants an integer. I tried to do it this way but _intDLocation = "" throws an exception Dim _dLocation As String = udDefaultLocationTextEdit
我有一个更新函数，通过数据集更新一个sql server数据库表。 表中的一个字段是一个整数并接受空值。 所以当我填充更新函数时，我需要一种在函数需要一个整数时输入null的方法。 我试图这样做，但_intDLocation = ""引发异常 Dim _dLocation As String = udDefaultLocationTextEdit.Text Dim _intDLocation As Integer If _dLocation <> "" Then _intDLocation = Integer.Parse(udDefaultLoc
In Perl (and other languages) a conditional ternary operator can be expressed like this: my $foo = $bar == $buz ? $cat : $dog; Is there a similar operator in VB.NET? Depends. The If operator in VB.NET 2008 acts as a ternary operator. This was just introduced, prior to 2008 this was not available. Here's some more info: Visual Basic If announcement Example: Dim foo as String = If(bar
在Perl（和其他语言）中，一个条件三元运算符可以表达如下： my $foo = $bar == $buz ? $cat : $dog; 在VB.NET中是否有类似的运算符？ 依靠。 VB.NET 2008中的If运算符充当三元运算符。 这是刚刚推出的，在2008年之前还没有。 这里有一些更多的信息：Visual Basic如果公告 例： Dim foo as String = If(bar = buz, cat, dog) iif一直在VB中可用，即使在VB6中也是如此。 Dim foo as String = iif(bar = buz, cat, dog)