我想在用户输入时验证文本字段的输入。这个功能工作正常，但是我想限制验证，因为它正在点击外部API。我想仅在用户未输入750毫秒后才执行验证。
ATM我只是使用它：
private void Configure_Load(object sender, EventArgs e)
{
endpointBox.KeyUp += EndpointBox_KeyUp;
}
void EndpointBox_KeyUp(object sender, KeyEventArgs e)
{
TestHTTP200(endpointBox.Text);
}
答案 0 :(得分：1)
您需要一个等于JavaScript的SetTimeout方法的方法。当用户提供更多输入时，可以取消此操作：
代码取自here。
public static IDisposable SetTimeout(Action method, int delayInMilliseconds)
{
System.Timers.Timer timer = new System.Timers.Timer(delayInMilliseconds);
timer.Elapsed += (source, e) =>
{
method();
};
timer.AutoReset = false;
timer.Enabled = true;
timer.Start();
// Returns a stop handle which can be used for stopping
// the timer, if required
return timer as IDisposable;
}
然后，您可以在密钥处理程序中使用它：
void EndpointBox_KeyUp(object sender, KeyEventArgs e)
{
IDisposable timeout = SetTimeout(() => TestHTTP200(endpointBox.Text), 750);
if (this.currentTimeout != null) {
this.currentTimeout.Dispose();
this.currentTimeout = timeout;
}
}
至少这是基本原则，每次用户输入你重新启动750毫秒超时来做你的事情，并取消任何待定的计时器。
更新：完整的代码示例：
public partial class Form1 : Form
{
private IDisposable currentTimeout;
public Form1()
{
InitializeComponent();
}
private void EndpointBox_KeyUp(object sender, KeyEventArgs e)
{
IDisposable timeout = TimerHelper.SetTimeout(() => TestHTTP200(EndpointBox.Text), 750);
if (this.currentTimeout != null)
{
this.currentTimeout.Dispose();
this.currentTimeout = timeout;
}
}
private void TestHTTP200(string text)
{
//...
}
}
public class TimerHelper
{
public static IDisposable SetTimeout(Action method, int delayInMilliseconds)
{
System.Timers.Timer timer = new System.Timers.Timer(delayInMilliseconds);
timer.Elapsed += (source, e) =>
{
method();
};
timer.AutoReset = false;
timer.Enabled = true;
timer.Start();
// Returns a stop handle which can be used for stopping
// the timer, if required
return timer as IDisposable;
}
}
答案 1 :(得分：1)
使用Timer控件
System.Windows.Forms.Timer myTimer = new System.Windows.Forms.Timer();
private void Configure_Load(object sender, EventArgs e)
{
endpointBox.KeyUp += EndpointBox_KeyUp;
myTimer.Tick +=new EventHandler(OnTimedEvent); //EDIT: should not be `ElapsedEventHandler`
myTimer.Interval=750;
}
void EndpointBox_KeyUp(object sender, KeyEventArgs e)
{
myTimer.Stop();
myTimer.Start();
}
private void OnTimedEvent(Object myObject,EventArgs myEventArgs)
{
myTimer.Stop();
TestHTTP200(endpointBox.Text);
}
答案 2 :(得分：0)
wrap_content这就是你如何使用这个课程using System;
namespace Azine_Library.Misc
{
/// <summary>
/// Represents a way to delay something, eg. something an event handler does, update-ion of a control, object or to run a method, This class '<see cref="DelayUpdate"/>'
/// is intended to be used as a delayer of some sort and contains an event, '<see cref="PushUpdate"/>' that would be subcribed to an event handler where then the code
/// intended to be delayed would go. This object also contains a method, '<see cref="delay"/>' that when called delays the code written/located within the event handler
/// that is handling the '<see cref="PushUpdate"/>' event. The method, <see cref="delay"/> should be called from an event handler or a method of some sort that would orginally
/// execute the code written/located within the event handler described above also. An example of how this object can interact with another object is described and documented in great detail
/// within the documentation for "Azine_Library", also an example program is available with the documentation.
/// </summary>
public class DelayUpdate
{
// Written, 17.06.2017
#region Fields / Properties
/// <summary>
/// Occurs when the provided time (interval:) has elapsed
/// </summary>
public event EventHandler PushUpdate;
/// <summary>
/// READONLY. the amount of times the timer has ticked since the last call to delay, (DelayUpdate.delay).
/// </summary>
public int updateCounter
{
get;
private set;
}
/// <summary>
/// The amount of time [this] waits for until it pushes the update. (Milliseconds). default value: '500'.
/// </summary>
public int interval
{
get;
set;
}
/// <summary>
/// Holds the amount of times [this] raises the "DelayUpate.PushUpdate" event every call to DelayUpdate.delay() method. default value: '1'.
/// </summary>
public int updatesPerPush
{
get;
set;
}
private System.Diagnostics.Stopwatch stopWatch;
private System.Windows.Forms.Timer timer;
#endregion
#region Constructors
/// <summary>
/// Initializes a new instance of type, 'DelayUpdate'; sets the classes' properties to the defaults.
/// </summary>
public DelayUpdate()
{
//Initializing Variables
this.updateCounter = 0;
this.interval = 500;
this.updatesPerPush = 1;
this.stopWatch = new System.Diagnostics.Stopwatch();
this.timer = new System.Windows.Forms.Timer();
//Sub-ing Events
this.timer.Tick += this.Timer_Tick;
}
#endregion
#region Methods
/// <summary>
/// Delays the raising of the event, PushUpdate; call this method when a property of an object has changed. eg, TextBox.TextChanged => DelayUpdate.delay();
/// </summary>
public void delay()
{
// Written, 13.06.2017
this.timer.Start();
this.stopWatch.Restart();
this.updateCounter = 0;
}
#endregion
#region Events
/// <summary>
/// Raises the 'DelayUpdate.PushUpdate' event.
/// </summary>
private void onPushUpdate()
{
//Written, 26.05.2017 : 5:22pm
if (PushUpdate != null)
PushUpdate.Invoke(this, new EventArgs());
}
#endregion
#region Event Handlers
private void Timer_Tick(object sender, EventArgs e)
{
// Written, 13.06.2017
if (this.stopWatch.ElapsedMilliseconds > this.interval)
{
if (this.updateCounter < this.updatesPerPush)
{
this.timer.Stop();
this.onPushUpdate();
}
this.updateCounter++;
}
}
#endregion
}
}
：
假设您有一个WinForm，它在目录中搜索有文本框的文件，＆＃34; search_textBox＆＃34;并附加了一个textChanged事件处理程序：
DelayUpdate.cs您可以引用该类namespace DelayUpdateExample
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
this.search_textBox.TextChanged += this.Search_textBox_TextChanged;
}
private void Search_textBox_TextChanged(object sender, EventArgs e)
{
}
}
}
并初始化它。如此订阅DelayUpdate.cs事件：
DelayUpdate.PushUpdate在textChanged事件处理程序中，您可以像这样调用private DelayUpdate delayUpdate;
public Form1()
{
InitializeComponent();
this.delayUpdate = new DelayUpdate()
{
interval = 500,
updatesPerPush = 1,
};
this.delayUpdate.PushUpdate += this.DelayUpdate_PushUpdate;
this.search_textBox.TextChanged += this.Search_textBox_TextChanged;
}
private void DelayUpdate_PushUpdate(object sender, EventArgs e)
{
throw new NotImplementedException();
}
..
DelayUpdate.delay()然后，您想要延迟的代码会进入您订阅的private void Search_textBox_TextChanged(object sender, EventArgs e)
{
this.delayUpdate.delay();
}
。像这样：
DelayUpdate_PushUpdate(object, EventArgs)