Converting A String Variable To A Property Type
Aug 28, 2009I have in my My.Settings four settings [code] now I want to get the value of the current setting from the My.Settings.SettingName. [code]
View 1 RepliesI have in my My.Settings four settings [code] now I want to get the value of the current setting from the My.Settings.SettingName. [code]
View 1 RepliesWe have an object with properties, and a a SQL database we're reading in, to create a list of objects, with columns corresponding to each property.if a column is missing from the database (e.g. caused by an outdated version of the database), we want to assign a default value to it.I've created a dictionary, mapping the column name to its default value (both strings).However, I was wondering if it was possibly to somehow convert the column name (string) to an object property (e.g. the string "name" to AnObject.name?), as the property and column name are generally the same.I tried to use GetType().GetPropert("column name"), but I can't seem to do assignments through that)Alternately, is it possible to somehow create a dictionary, storing the object property as the key (and the column name and default value in a struct), and then grabbing it after.?
View 1 RepliesI'm trying to add data into a datagridview cell but I keep on getting a data type error.[code]Value of type 'Char' cannot be converted to 'System. Windows.Forms.DataGridViewCell'.[quote]
View 2 RepliesI'm trying to delete the 2 last characters of a string if they are "||". This is my
Dim MyReader As Microsoft.VisualBasic.FileIO.TextFieldParser
MyReader = My.Computer.FileSystem.OpenTextFieldParser(playlist)
Dim TextFields As String() = MyReader.ReadFields()
Dim last As String = TextFields.Last
If last.Substring(last - 2) = "||" Then
last.Remove(last - 2)
End If
But it gave me the following error on the highlighted line:
"The converting from the string to the type Double is not valid."
I'm not sure if i titled this question properly or am asking it properly, but here goes.I've got serialized objects (in XML) stored in a database, along with a string/varchar indicating the type.
[Code]...
I have a program that calculates commission, but if the commission is nothing then I do not want it to show a zero commission. I want a message box to show a message that there is no commission earned.
View 1 RepliesI have a problem involving late binding, and I absolutely cannot for the life of me figure out how to fix it. I have spent hours researching the problem to no avail, so I am turning to stackoverflow as a last resort.The problem is pretty much this: I am creating a grocery list application. I have a class named Item which stores the name, price, quantity, and description of an item on the grocery list. I have a module named ListCollection which defines a Collection of Item objects. I have created an Edit form which will automatically display the currently selected ListCollection item properties, but whenever I attempt to fill the text boxes, it tells me that Option Strict disallows late binding. I COULD take the easy route and disable Option Strict, but I'd prefer to figure out what the problem is so I know for future reference.I shall paste pertinent code here. (Late binding error is in EditItem.vb)
[code]...
I have tried declaring a String variable and assigning the Item property to that, and I have also tried grabbing the value directly from the List item (not using the Get function), and neither of these made a difference.
I want to see if a variable's type is string or double type. How to do it in vb.net immediate window?
View 1 RepliesI have this function:
Public Sub DoStuff(ByVal type as System.Type, ByVal value as Object)
End Sub
The 'value' argument is always an array of the same type as 'type'. How can I loop through the values of the array?
I'd like to be able to do something like this:
DoStuff(GetType(Integer), New Integer(){1,2,3})
Public Sub DoStuff(ByVal type as System.Type, ByVal value as Object)
//Strongly types arr as Integer()
[Code].....
I'm aware that questions like this have been asked before and I doubt it's possible, but I just wanted to make 100% sure that it isn't.In VB.net or C# (either language, it doesn't matter), I want to cast a variable to a type represented by another Type variable. Here's an example of the kind of code that would be needed in C#:
Object castMe = new Foo();
Type castTo = typeof(Foo);
Foo beenCast = (castTo.GetRepresentedType())castMe;
[code].....
i have a column in datagridview composed of numeric as well as aphanumeric. What i want is when the user sorts the column, it will be sorted according to its number value, 1,2,3,4,5,6,7,8,9,10. However it my current module, the program sorts basing the first digit of the column. like 1,10,11,12,2,3,30,31.
i was thinking of converting the type to number so that it will be arrange properly, is this possible in the datagridview to covert type? because i saw only a readonly property celltype? i have also tried casting it in the sql query itself to INT but it did not work.
Now I have the need to get a current value from a bindingsource in a property of a user control.In a previous thread I had tracked down the "Object variable or With block variable not set" to the return in the Get block of a property. At the time I was only using the Set so I just commented out the offending code until I needed it.
[Code]...
The error does not occur during a system compile, only upon saving the container object of the user control. As I said the Set works correctly, only the Get causes the error.I would like to know what I am missing/misunderstanding and am open to other suggestions of handling retrieving the current value of a bindingsource in a user control.
I'm looking for a way to search a string variable for two words and copy the text in between them into another variable. This needs to be done as many times as the match occurs.
View 3 RepliesDim Button As ToolStripButton = New ToolStripButton
Button.image = Icon.ExtractAssociatedIcon(exefile)
I try that code, and it just throws me the error that type Icon cannot be converted to Image. So how do i get around this? And does "ExtractAssociatedIcon(exefile)" work on exe files? Admittedly i don't really know what im doing
Dim Button As ToolStripButton = New ToolStripButtonButton.image = Icon.ExtractAssociatedIcon(exefile)I try that code, and it just throws me the error that type Icon cannot be converted to Image.So how do i get around this? And does "ExtractAssociatedIcon(exefile)" work on exe files?
View 3 RepliesI want to assign an object property by referencing the property dynamically, with a variable name
i.e.
dim propName as string
staticObjectName.propName = 'whatever
Public Class Form1
Dim x, c, number(0 To 19) As Integer
Dim s As Integer
[CODE]...
The variables in the brackets [example] do not actually have brackets in them in the original code. These are where the issues are. For both variables, it says, "The type for variable [variable] will not be inferred because it is bound to a field in an enclosing scope. Either change the name of [variable], or use the fully qualified name (for example, 'Me.[variable]' or 'MyBase.[variable]')." Now, I'm not entirely sure if this is a stupid question or not, as I'm used to VB '98 because that's what we use in my programming class at High School. let me know why this won't work.
-Note: The intention of this program is to continually loop the generation of numbers for this list until I tell it to stop. Button1 ends the program, Button2 generates the list one time only, Button3 is supposed to loop the generation of the list, and Button4 is supposed to end the loop, but not the program.
I am looking for a good resource on variable naming conventions to illustrate variable type and where variables are declared. So I will have public variables, Private variables, private or local variables. I also may want to declare variables with the same name in different class code (i.e. in the code behind different forms). I am assuming good coding would dicatate a prefix for declaration location.
View 4 RepliesI have the following code that I am using to parse out a test file. I am getting variable conversion error in Sub Main() when I assign file = Read(). The return value of Read() is a TextFieldParser type. How do I assign the proper variable type to "file" so I can write the output to a text file?
Function Read()
Using MyReader As New FileIO.TextFieldParser("C:UsersColinDesktopParse_Me.txt")
Dim currentRow As String
[Code].....
E.g. how do I get VB.Net to statically type a local variable to be the static type of the expression on the right had side of the assignment?
View 1 RepliesI want to use explicit conversion (CType function in VB.NET) to convert the variable d from double type to integer type and store the result as 132.
Imports System.Console
Module Module1
Sub Main()
[CODE]...
This is my code. But Visual Basic tells me an error: Error1Type 'i' is not defined.C:\Users\mihaispr\Desktop\Conversie explicita\Conversie explicita\Module1.vb1922Conversie explicita
Writing an asp.net mvc app and i have something like this...
Public Class AA
'... has some variables...
End Class
Public Class BB
[code]....
So, now in my program, i just want to copy object of type AA to an empty variable of type BB?it makes sense to do this, as i expect all the fields in AA type object to be copied to the newly created BB type object, and the ExtraVariable in the BB type object i would (will) just assign a value to it later (after the copy) on my own time!!I know copying BB type to AA type would not be appropriate as there would be lost data!But im trying to copy AA to BB, I've used both DirectCast and CType to do this, and i keep getting "unable to cast" error!
Note: I'm using vb.net (but can read c#, no problems)
I have a requirement where I need to have a "type safe" way of accessing property names, without actually instantiating an object to get to the property. To give an example, consider a method that takes as arguments a list of IMyObject and a string that represents a property name (a property that exists in IMyObject).
The methods implementation will take the list and access all the objects in the list using the property name passed... for some reason or another, we won't dwell on that!!
Now, I know that you can do this using an instantiated object, something like ...
Dim x as MyObject = nothing
Dim prop As PropertyInfo = PropHelper.GetProperty(Of MyObject)(Function() x.MyProperty)
Where my helper method uses reflection to get the name of the property as a string - there are numerous examples of this flying around on the web!
But I don't want to have to create this pointless object, I just want to do something like MyObject.MyProperty! Reflection allows you to iterate through a types properties and methods without declaring an object of that type... but I want to access a specific property and retrieve the string version of its name without iteration and without declaring an object of that type!
The main point here is that although I am trying to get the property name as a string... this is done at run time... at compile time, I want this to be type safe so if someone changes the property name, the compilation will break.
What's the C# equivalent of
<% dim name %>
so you can use it for web forms in PayPal API integration?
How do I convert, let's say, a variable such as X from radians to degrees. I am designing weather forecasting software and cannot get it to work. proper syntax and much obliged.
View 9 RepliesI am working in a form, and I had to this
Dim par1 as string = "something"
I want pass par1 to update sql statement, and I am not using AddParameter So, I had to add single quotes, the par1 will be
par1 = "'" + par1 + "'"
instead of doing the above, I was thinking in
par1 = par1.ToString.AddSingleQuote
or
par1 = par1.AddSingleQuote
Either to add "AddSingleQuote" to "ToString" method, or make it available for every variable of type "String" Can that be done?
I'm trying to wrap up a program I wrote in VB.NET and quick. I have a device that I am connected to through a serial port (COM4). It sent me 1056 binary bytes which I have stored in an array called newRecievedData. (see code below)
********** Start Code*********
Dim numberOfBytesToRead As Integer
numberOfBytesToRead = myComPort.BytesToRead
Dim newRecievedData(numberOfBytesToRead - 1) As Byte
[Code].....
I understand the concept of bytes and declaring variables to save on processing space. I understand that the max value that can be stored in a byte is 255. I cannot seem to wrap my head around my current issue. I don't have much experience working with byte manipulation.
[Code]...
I apologize in advance about asking a newbie question. I am a less-than-intermediate programmer who has done most of his work in VB6, and now trying to wrap my mind around the new concepts of the NET languages.In VB 2010, I have a Structure called "Direction", with one data member -- an integer named "Value". It's supposed to represent a value of degrees from 0 to 359.
Public Structure Direction
Private d As Integer
[code].....
Using the code
Dim dr As OleDbDataReader
Dim dbconn As New OleDbConnection
dbconn.ConnectionString =
"Provider=Microsoft.Jet.OLEDB.4.0;Data source=" & "C:MyData.mdb"
[code]....
I can extract
ColumnName = Item
ColumnSize = 80
DataType = System.String
But to write a Parameter I need to convert this to
UpDateCmd.Parameters.Add("Item", OleDbType.BSTR, 80).Value
Is there an easier way of converting DataType = System.String to OleDbType.BSTR than having to make a list with Select Case?Or is there a method to find OleDbType.BSTR rather than reading DataType = System.String?I also tried
SchemaTable = dbconn.GetOleDbSchemaTable(System.Data.OleDb.
OleDbSchemaGuid.Columns, New Object() {Nothing, Nothing, "Auction"})
Dim RowCount As Int32
[code]....
But that also returns DataType = System.String.