Dataset.clear Method - What Does It Actually Means
May 13, 2009
I think I've misused this method and would like to know what it actually does.I 've looked it up on msdn forum and found this
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What does it mean by removing all the rows in all tables? Is it the datagridview table? When it says "removing", does it mean that it deletes everything?
The reason I misused it is because I thought dataset.clear means it flushes the record held in dataset.
When I click on the add new icon on bindingnavigator, a new form will appear, which allows me to insert data
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when I close the insert form, the parent form will be activated and datagridview will display the new record I just inserted. I thought the dataset.clear method helped display the new added record but then I realised I could do without the dataset.clear method.
I have a timer that runs every time by itself, and for the code the runs in it I would like to have it clear the dataset before it does anything, the timer runs every 10 seconds, so I tried to do dataset.clear but it would crash if the dataset had no values
I need to clear a dictionarybase collection have tried the below mentioned method but it gives me an error... any help please?? ( in the Public sub MClear....) here's the code:
Imports System.IO Public Class IPAddresses Inherits DictionaryBase
Supose i have two TextboxOne For normal Text and Second For After Replace textif i m Type some text in textbox 1 then Textbox2 show Its Replacement Text
' This example demonstrates the 'Console.CursorLeft and ' Console.CursorTop properties, and the[code].....
the code straight from the source <<< a couple of pages back thataway i'm getting a build error about the users ameappdataloca emporary projectsfile.exe not found.VB Express 2008 on Windows 7. how to output text to different parts of the screen.
i am making a program that can paint something.the painting code is easy to do, but i cannot find out how can i make the clearing of what i have drew.in this code u can see that i made it on the mouse click/down and while moving it it will draw a line.
private shouldpaint as boolean = false Private Sub Form1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseDown
In my main application i am trying to run Pre-defined Code blocks that the user has created. I would also like to send a DataSet as a parameter when the code is compiled. Is this possible. Currently I can pass in single values by assigning them as a string in the code wrapper through the <%= input %> expression. Then i compile this as source.
I must modify 2 columns in this dataset, based on a custom function value (a normal vb function), which parameter is an another column from the dataset.[code]...
I am looking for some guidance with the most optimal or efficient way to export a dataset to an excel file. I have searched the forums and found a number of methods to do this. However, the code I am currently using is very inefficient as it is itterating through the rows and columns to create the excel file. The app I am working on needs to be able to create 50 or so excel files each with 500+ rows and 40-50 columns. This method seems to inefficient for my use
I have two forms, a main display form with a Zedgraph Pane on it and a second form with a single ComboBox control, opened by a button click on the first form and having its ComboBox filled by the Labels of the curves currently being shown by the Zedgraph pane.The code below seeks to remove the curve selected in the ComboBox by clearing its points, but on the CurveList.Clear line, I always get a "Method not Implemented" error.
Private Sub rmvCurve(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles chnlSelectRmv.SelectedIndexChanged Dim curLabel As String
I am experiencing something very bizarre when I execute the Fill method of my adapter. I've been running this query for months and all of the sudden this is happening after I installed SP1 for Visual Studio 2008. For some reason several DataRows in 2 of the 3 tables within my DataSet have errors in them when I view them in debug mode using the DataSet Visualizer. Here is a picture of what I'm talking about
It does this to random rows. If I execute the Fill method the first time, rows (5-10) will have these errors. If I execute the Fill method again rows 12-23 are affected and so on. I have no idea what is happening here.
This is effected my DataGridViews, because they don't display any rows, because of the erros. I should also note that when I run the lines of code below in the Immediate Window it says the DataSet doesn't have errors.
I created a new query in the dataset designer. There are now 2 queries there. The original one and the new one.I also added named parameters in the Where clause of the 2nd query.This is the query in the new one:
What Does : Dim Array() as String means and what Dim Array as String() Means?If I pass a array to function like below:Public Sub Array_AddSomething(ByVal strEntry As Object, ByRef strArray() As Object)
i am still new in VB.net if someon can just help with these codes below: [code] what does the () after each one of these declaration means are they arrays?!
I saw something really strange today, that I have not seen before.I saw a variable declared as:Dim a as Long? I am obviously familiar with the Long datatype but what is Long?
Consider a MyForm class that contains a shadowed implementation of Show(). It also contains a CreateForm() method, which accepts an instance of the form and calls the shadowed sub:
in hyper teriminal when i press "ctrl+L" is to clear terminal screen how to write the code in vb.net? Hyperterminal is connecting to serial comport.when i try this it work and return line on debug
serialport.writeline ("at+cmgl=1")
i try this but not work and it still show some lines on debug
I've got a piece of code of a class. When initialised a new object is made on a picturebox. But what I don't know is how does the program know that the public property x and y means the coordinates of the object?
Private Sub TextBox4_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox4.KeyPress If (e.KeyChar < "A" OrElse e.KeyChar > "Z") Then e.Handled = True End If End Sub
If e.Handled = True means we can enter a to z and A to Z in textbox.If e.Handled = False then what it means??
If I increase the capacity of a given list, or add elements until count>capacity, does this mean the program is actually copying the entire list's contents to a new space in memory (similar to redim preserve with arrays)? If so, than I have really been hurting the performance of my lists, as before I was inserting and adding without a second thought. This seems a strong restriction on the dynamic abilities of lists.
way to clear textboxes in VB.Net and what is the difference between the two methods? I have also seen people be critical of folk using clear objects on their forms and i can see why but in this case, i am only learning.
