小编PiZ*_*zL3的帖子

当我做了某乙以下..任何人修改一个(我以为这样做会克隆从人,将B).我也不知道如果更改Person a将在链接后更改Person b.由于我的代码现在,我只能在一个方向看到这个.

Person a = new Person() { head = "big", feet = "small" };
Person b = a; 

b.head = "small"; //now a.head = "small" too   

现在如果我这样做了.人a变得完全分开.

Person b = new Person() { head = a.head, feet = a.feet };

现在,将此行为与C#中的其他内容进行比较时,这种方法很有意义.但是,对于大型物体,这可能会非常烦人.

有没有办法简化这个？

如:

Person b = a.Values;

如何将2个列表传递给Parallel.ForEach？

例:

List<Person> a = new List<Person>() { new Person(), new Person(), new Person() };
List<Car> b = new List<Car>() { new Car(), new Car(), new Car() };

//PSEUDO CODE
Parallel.ForEach(a, b, (person, car) => {
    //WORK ON person, WORK ON car
});  

我宁愿避免将Person和Car封装到Object容器中.这可能吗？

是否有更好/更准确/更严格的方法/方法来确定URL是否格式正确？

使用:

bool IsGoodUrl = Uri.IsWellFormedUriString(url, UriKind.Absolute);

不抓住一切.如果我输入htttp://www.google.com并运行该过滤器,它就会通过.然后我NotSupportedException打电话给我WebRequest.Create.

这个错误的网址也会使它超过以下代码(这是我能找到的唯一其他过滤器):

Uri nUrl = null;
if (Uri.TryCreate(url, UriKind.Absolute, out nUrl))
{
    url = nUrl.ToString(); 
}

如何让VS ListView在"设计"面板中填充示例数据？

我很难过.我做了很多阅读和谷歌搜索,无法找到一个可靠的答案.在VS Design面板中显示虚假数据将大大加快主题,因为我不必每隔几次更改就调试它.

这是我的代码:

XAML:

<ListView DataContext="{Binding}"
          Name="PeopleListView">
    <ListView.ItemTemplate>
        <DataTemplate DataType="Person">
                <WrapPanel>
                    <TextBlock Text="{Binding Path=FirstNameView}"/>
                    <TextBlock Text="{Binding Path=LastNameView}" />
                </WrapPanel>
        </DataTemplate>
    </ListView.ItemTemplate>
</ListView>

采集:

public class People : ObservableCollection<Person>
{
    public People()
    {
        this.Add(new Person() { FirstName = "John", LastName = "Doe" });
        this.Add(new Person() { FirstName = "John", LastName = "Doe" });
        this.Add(new Person() { FirstName = "John", LastName = "Doe" });
    }
}

主要:

private People PList;

public MainWindow()
{
    this.PList = new People();
    PeopleListView.ItemsSource = …

假设我有50个我开始使用的请求BeginGetResponse.

如何查看每个请求的状态？
以及如何取消它(有时它们会挂起)？
以及如何在完成或取消所有请求后执行操作？

如何将IAsyncResult传递给AsyncCallback？

示例代码:

//Usage
var req = (HttpWebRequest)iAreq;
req.BeginGetResponse(new AsyncCallback(iEndGetResponse), req);

//Method
private void iEndGetResponse(IAsyncResult iA, bool iWantInToo) { /*...*/ }

我想传递示例变量bool iWantInToo.我不知道如何添加它new AsyncCallback(iEndGetResponse).

我将如何通过在 Person 中选择的字典值对其进行排序？

示例：按“汽车”值降序排列“人”的顺序列表。

用那些奇特的 lambda/linq 方程之一可以做到吗？

public class People 
{
    List<Person> Persons { get; set; }
}

public class Person
{
    public Dictionary<string, string> cars { get; set; } 
    public Dictionary<string, string> houses { get; set; } 
    public Dictionary<string, string> banks { get; set; }
}

................

People people = new People();

people.Persons = new List<Person> 
{
    new Person 
    {
        cars = new Dictionary<string, string> { { "volvo", "340050" }, { "bmw", "50545000" } }, 
        houses = new Dictionary<string, …

private void tbLog_TextChanged(object sender, TextChangedEventArgs e)
{
    //Get only NEW text added to Log
}

/*
    LOG
    old message...
    old message...
    old message...
    old message...
    NEW message...
    NEW message...
    NEW message...
    NEW message...
    NEW message...
*/  

如何仅从 TextBox 获取新文本？

有没有办法缩短我的 BackgroundWorker.CancellationPending 检查站？

例如,有没有办法return像下面的示例代码一样进行封装？:

//REAL CODE (CURRENTLY USE THIS)
if (this.TW.CancellationPending) 
    return; 

//PSEUDO REPLACEMENT CODE
this.CkPt(CurrentMethod); //PSEUDO USAGE 
    //^^^ PARAMETER IS A REFERENCE TO THE CURRENT METHOD, SIMILAR TO `this` FOR AN OBJECT  
//OR MAYBE AN EXTENSION METHOD WOULD LOOK CLEANER
CurrentMethod.CkPt(); //PSEUDO USAGE

private void CkPt(Method m) //PSEUDO METHOD
{
    /*
        POSSIBLY PERFORM OTHER CHECKPOINT TASKS HERE
    */
    if (this.TW.CancellationPending) 
        m.return/*FROM METHOD THAT CALLED ME*/;
}  

我试图使这样的多检查点情况更具可读性:

//PSUEDO METHOD 
//DO NOT TAKE THIS AS REPEATING CODE
//IT …

有没有办法在C#中执行此操作而不为每个var类型设置重载的新方法？

$box = !empty($toy) : $toy ? "";  

我能想到的唯一方法是:

if (toy != null)
{
    box += toy; 
}  

或这个:

public string emptyFilter(string s) ...
public int emptyFilter(int i) ...
public bool emptyFilter(bool b) ...
public object emptyFilter(object o) 
{
    try 
    {
        if (o != null)
        {
            return o.ToString(); 
        }
        else 
        {
            return ""; 
        }
    }
    catch (Exception ex)
    {
        return "exception thrown": 
    }
}

box += this.emptyFilter(toy);

我基本上想检查以确保变量/属性设置/不为空/存在/有值/等等...并返回它或""没有一些像上面这样的代码的荒谬.