Questions tagged [eventhandler]
In object-oriented programming languages (such as C++, Lazarus Pascal or Visual Basic), visual objects (or components) can respond to *events* (usually) by the user. An event handler is the block of code that runs when an event occurs. Eg: *Onclick* event for a command button.
eventhandler
818
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How to write Java Script arrow functions in regular function syntax?
I need help to rewrite some arrow functions to regular functions but right now my brain is totally stucked, I have some example code here from a rock paper scissors game I got from kyle, how would it ...
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1
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588
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Task.Run invoking an EventHandler. Is it correct?
I am writing unit tests for an async method and I think I should avoid .Invoke inside Task.Run in the next function.
Here is the current code under test:
public class Foo
{
public event EventHandler&...
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Why don't we create an Event Handler delegate for binding a handler with an event when programmatically creating an event handler?
I am creating a Windows Form application in Visual Studio using C#. I am having trouble understanding the concept of Event Handler Delegates.
If I create an event handler for an event using the ...
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How do I change the text of a System.Windows.Forms.Label from a public static void button_click event?
More details:
Assume I am creating a form and a button and a label in the main function, and I want the label text to change when I click on the button. I am getting an error that the label is outside ...
3
votes
2
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How do I set the correct type for a click handler when using Svelte with TypeScript?
I am using Svelte with TypeScript. I have a button:
<button on:click|preventDefault={clickHandler}>
Click me
</button>
I am trying to set the correct type for the click handler.
export ...
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Assigning event handler with arguments to events using arrow functions
In the below snippet,during a click event, the arrow function gets called. Now, this arrow function in turn runs the code in its body. Now since callme() is a single line statement, so it should ...
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63
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Mocking Event handling will not cover delegate function assigned
Trying to mock an EventHandler for an Event raised from another class. However, when I run the test, the test does not cover the code that implemented inside the handler.
Test
[Fact]
public void ...
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4
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0
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How to Solve Event Hander Nullable Warning Problem
button1.Click += new System.EventHandler(button1_Click);
For this code above the VS gives warning of CS8622 for "button1_Click" in the EventHandler: https://learn.microsoft.com/en-us/dotnet/...
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5
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358
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How to differentiate between buttons using the same class using a function?
I have this simple page set up which will add or remove a hidden class on an element when either button is clicked. The code works fine as is, but I know that it's very inefficient. I plan on adding ...
0
votes
1
answer
722
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Event.target types for name input in FromHandler with TypeScript
I have a simple form in a React SPA with typescript.
I'm going to make this form processing simple, without adding component state and so, just to get value from the named input, name = 'gameId'.
...
1
vote
3
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adding an eventhandler to datagridview
I am trying to add a key event handler to a Datagridview.
I have added this (below) to my code:L
private void DgvDb_KeyUp(object sender, KeyEventArgs e)
{
colI = DgvDb.CurrentCell.ColumnIndex;
...
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1
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624
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Javascript event listener structure
I’m working on a code to get the index of a clicked element so it can add or remove a class to display or hide the information. For it I used for for iteration. But I don’t understand why is there an (...
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Does a bodiless function in JavaScript prevent the default of an event?
I set the "passive" Parameter of a touchmove event to true and therefore can't call e.preventDefault() inside the function. But I need the function to prevent the default behaviour of the ...
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Updating state twice when the button is clicked, React
I want to create simple 2048 game application. My initial board is composed of 16 array elements.
The generate() function generates a value of '2' in a random empty element
It works just fine and ...
0
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0
answers
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How can I stop the app from stopping every time I click on a button to leave the current slideshow to a new activity
I have a simple slideshow
with 20 slides and a 5 sec. time
delays using the
handler class, and the media
player class that plays a different
sound on each slide. There is a
button on this activity ...
