Implementation of the progress bar (attribute change notification mechanism) for developing the WPF mass mailing Tool

Some time ago, I took the time to use WPF as a mass mailing tool. Next I would like to use two or three blogs to share with you the puzzles and accumulated experiences in the development process, although familiar with winform development, there is a big difference between them after all-from the presentation of the interface to internal control. The title of this blog is clear. What I want to talk about is the implementation of the progress bar (attribute change notification mechanism!
 

The progress bar is easy to implement in winform,CodeAs follows:

 1           Private   Void Button#click ( Object  Sender, eventargs E)  2   {  3               Int Num = 100  ;  4              This . Progressbar1.maximum = Num;  5               For ( Int I = 0 ; I <= num; I = I + 10  )  6   {  7                   This . Progressbar1.value = I;  8 Thread. Sleep (1000  );  9   }  10 }

The seemingly normal logic is ineffective in WPF. The reason is tested and analyzed: it should beControls and interfaces in winform are in the same thread, while those in WPF are not in the same thread..

Now let's start with the topic and talk about the implementation of the progress bar (attribute change notification mechanism) in WPF --

Sending result Information Entity class

 1   Using  System;  2   Using  System. Collections. Generic;  3  Using  System. LINQ;  4   Using  System. text;  5   Using  System. componentmodel;  6   7   Namespace  Emailbatchsend  8   {  9       ///   <Summary> 10       ///  Sending result Information Entity  11       ///   </Summary>  12       Internal   Class  Sendresult: inotifypropertychanged  13   {  14           Public   Event  Propertychangedeventhandler propertychanged; 15   16           Private   String _ Progressbarnumshow = String  . Empty;  17           ///   <Summary>  18           ///  Display progress bar numbers  19           ///   </Summary>  20          Public   String  Progressbarnumshow  21   {  22               Get  23   {  24                   Return   This  . _ Progressbarnumshow;  25   }  26               Set 27   {  28                   This . _ Progressbarnumshow = Value;  29 Onpropertychanged ( "  Progressbarnumshow  "  );  30   }  31   }  32   33          Private   String _ Sendresultmes = String  . Empty;  34           ///   <Summary>  35           ///  Send result message  36           ///   </Summary>  37           Public   String Sendresultmes  38   {  39               Get  40   {  41                   Return   This  . _ Sendresultmes;  42   }  43               Set  44   { 45                   This . _ Sendresultmes = Value;  46 Onpropertychanged ( "  Sendresultmes  "  );  47   }  48   }  49   50           Private   String _ Sendfailemails = String  . Empty;  51           ///   <Summary>  52           ///  Failed message sending  53           ///   </Summary>  54           Public   String  Sendfailemails  55  {  56               Get  57   {  58                   Return   This  . _ Sendfailemails;  59   }  60               Set  61   {  62                   This . _ Sendfailemails = Value;  63 Onpropertychanged ( "  Sendfailemails  "  );  64   }  65   }  66   67           Private   Int  _ Currentsendnum;  68          ///   <Summary>  69           ///  Number of currently sending messages  70           ///   </Summary>  71           Public   Int  Currentsendnum  72   {  73               Get  74  {  75                   Return   This  . _ Currentsendnum;  76   }  77               Set  78   {  79                   This . _ Currentsendnum = Value;  80 Onpropertychanged ( " Currentsendnum  "  );  81   }  82   }  83   84           Private   Bool _ Sendcontrolisenabled = True  ;  85           ///   <Summary>  86          ///  Whether the mail sending control is available  87           ///   </Summary>  88           Public   Bool  Sendcontrolisenabled {  89               Get  90   {  91                   Return   This  . _ Sendcontrolisenabled; 92   }  93               Set  94   {  95                   This . _ Sendcontrolisenabled = Value;  96 Onpropertychanged ( "  Sendcontrolisenabled  "  );  97  }  98   }  99   100           Private   Void Onpropertychanged ( String  Propertyname)  101   {  102               If ( This . Propertychanged! = Null  ) 103                   This . Propertychanged ( This , New  Propertychangedeventargs (propertyname ));  104   }  105   }  106 }

Use on the Interface

Figure 001

The code above shows that the sendresult class has implementedInotifypropertychanged -- this interface is used to send a notification to the client that a property value has been changed,The interface is defined as follows:

 1   Namespace  System. componentmodel  2   {  3       //  Abstract:  4      //  Sends a notification to the client that the property value has been changed.  5       Public   Interface  Inotifypropertychanged  6   {  7           //  Abstract:  8           //  Occurs when the attribute value is changed.  9           Event Propertychangedeventhandler propertychanged;  10   }  11 }

This interface has only one propertychanged event definition. As the name suggests, this event is triggered when the property value changes and does not need to be implemented. I'm curious about its internal implementation. Focus on the red and purple areas in Figure 001. The current value of the progress bar and the available status of the send button are set by {binding attribute name, the usage of {binding attribute name} is common in WPF. It is similar to <% # eval ("attribute name")> in the data binding control of webform, similarly, you also need to set a datasource-like dashboard for the control to associate the data binding of the control with a specific data object to implement corresponding functions.

 
1Sendresult =NewSendresult ();2 This. Progressbar. datacontext = sendresult;
 

The above code is equivalent to setting the progressbar data source, but in WPF, it has another name: datacontext data context. Almost all WPF controls have datacontext, data Binding is supported.

The progress bar has been implemented as follows:

This is because you are not proficient in WPF. If you have any misunderstandings, I hope you can point out or talk about your own opinions. If you are interested, you can leave a message to exchange ideas and learn from each other!