event-handling

问题 I've created an application that need to be in a safe state and so I want to follow the power status of the computer in background. If the battery level (if any) is low or critical, I wouldn't allow the user to continue using the application and quit all properly. First of all, I'm astonished that no such event exists in order to detect the change. You need always to check the PowerStatus manually. So, I've created a wrapper around it, something like this : using System; using System.Windows

问题 This works: XAML: <Window x:Class="Test239992.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="Window1" Height="300" Width="300"> <StackPanel> <TextBlock Tag="1" Text="Customers" MouseDown="Handle_Click"/> <TextBlock Tag="2" Text="Appointments" MouseDown="Handle_Click"/> </StackPanel> </Window> Code Behind: using System; using System.Windows; using System.Windows.Controls; using System.Windows.Input;

问题 I'm looking for the best way to handle a change of index being selected on a ASP.net RadioButtonList (C# code behind). I have 3 list items. For the first one, I want it to show a hidden asp:textbox on the page, whereas the other 2 will hide the textbox. //asp.net side <asp:RadioButtonList ID="_indicatorAckType" runat="server" RepeatDirection="Horizontal" enabled="true" OnSelectedIndexChanged="onAckTypeChanged"> <asp:ListItem Text="None" /> <asp:ListItem Text="SHOW" /> <asp:ListItem Text="HIDE

问题 I'm trying to update the lat/lng value of a marker after it is moved. The example provided uses a popup window to display the lat/lng. I have a "dragend" event listener for the marker, but when I alert the value of e.latlng it returns undefined. javascript: function markerDrag(e){ alert("You dragged to: " + e.latlng); } function initialize() { // Initialize the map var map = L.map('map').setView([38.487, -75.641], 8); L.tileLayer('http://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {

问题 Code which tries to mimic the real dynamic condition clear all; close all; hFig2=figure('Units','inches', 'Name', 'Time'); hax2=axes(hFig2); movegui(hFig2, 'southeast'); index=1; while (index < 7); hFig2=figure(hFig2); u=0:0.01:1+index; plot(hax2, u); % Give columns 1xXYZ to Matlab hold on; axis(hax2, 'xy'); axis(hax2, [0 (size(u,2)/1 - 0) min(u) max(u)]); % to maximise size axis(hax2, 'off'); % no ticks index=index+1; pause(1); hold off; drawnow end; Logs 1 hax2 in more dynamic condition,

问题 I have a dropdown list that contains a collection of names. My entire names list is very large (over 2,000) so I would like to pair down the names in the drop down list to those starting with the same letter. To do this I would like to have 26 links all on the same line, one for each letter in the alphabet .. A|B|C|D|E|F|G|H|I|J|K|L|M|N|O|P|Q|R|S|T|U|V|W|X|Y|Z The idea being that the user clicks on the letter they are interested in and the stored procedure that obtains the list of names is re

问题 The TabLoad() function doesn't seem to be working on clicking of this dynamic button. The aim of this button click event is that it deletes text from a text file and loads the form again. Below is the complete code. The TabLoad() function is in the NextDelbtn_Click sub at the end. Also any suggestion regarding change of code is appreciated. Imports System.IO Public Class Form1 Dim str As String Dim FILE_NAME As String = "D:\1.txt" Dim file_exists As Boolean = File.Exists(FILE_NAME) Private

问题 i got a question regarding sharepoint workflows and event receivers. i got an event receiver that is setting metadata on an element. after that, i use a workflow to copy item metadata to a list. unfortunately the workflow does not copy the metadata set by the event receiver. i think because it is executed before the event receiver. is there a possibility to change the order, so that the workflow will execute after the event receiver? the receiver ist bound to the ItemAdded and ItemUpdated

问题 What is the difference between var events = require('events'), emitter = new events.EventEmitter(); and var emitter = require('events').EventEmitter; or EventEmitter is pretty forgiving in using/not using new and () ? 回答1: Your second example doesn't call EventEmitter at all. emitter ends up being a reference to the function, not an object created by calling it. If you meant to have () on that: var events = require('events'), emitter = new events.EventEmitter(); vs var emitter = require(

问题 I am trying to programmatically add an unspecified amount of new UserControls to a form. One will be added every time an entry is selected in a ComboBox contained within the UserControl. Problem is, the SelectedIndexChanged event fires completely erratically. Sometimes twice, sometimes 3 times, etc., but never just once. No matter how many times I set the combobox's SelectedIndex to -1, it fires at least once with a SelectedIndex of 0. Sometimes the Itemselected event fires multiple times