CSLA.Net学习（3）INotifyPropertyChanged和IDataErrorInfo

浏览数：278 / 时间：2015年06月09日

今天晕晕糊糊的看CSLA.net，希望能找到验证数据正确性的方法，还是摸索出了INotifyPropertyChanged, IDataErrorInfo接口的使用方法，通过INotifyPropertyChanged实现了响应属性改变的事件，通过 IDataErrorInfo接口实现了在DataGridView或者GridControl中显示验证信息。

先看一个数据实体的抽象类：

 1  public abstract class BaseModel : INotifyPropertyChanged, INotifyPropertyChanging, IDataErrorInfo
 2     {
 3         protected BusinessRules mBusinessRules = new BusinessRules();
 4 
 5         public event PropertyChangedEventHandler PropertyChanged;
 6 
 7         public event PropertyChangingEventHandler PropertyChanging;
 8 
 9         public BaseModel()
10         {
11             mBusinessRules.info = this;
12             AddRule();
13         }
14 
15         public virtual void AddRule()
16         {
17             
18         }
19 
20         protected virtual void PropertyHasChanged(string name)
21         {
22             var propertyNames = mBusinessRules.CheckRules(name);
23 
24             foreach (var item in propertyNames)
25                 OnPropertyChanged(item);
26         }
27 
28         protected virtual void OnPropertyChanged(string propertyName)
29         {
30             if (PropertyChanged != null)
31                 PropertyChanged.Invoke(this, new PropertyChangedEventArgs(propertyName));
32 
33         }
34 
35         protected virtual void OnPropertyChanging(string propertyName)
36         {
37             if (PropertyChanging != null)
38                 PropertyChanging.Invoke(this, new PropertyChangingEventArgs(propertyName));
39 
40         }
41 
42         #region IDataErrorInfo
43 
44         string IDataErrorInfo.Error
45         {
46             get
47             {
48                 return "Hello";
49             }
50         }
51 
52         string IDataErrorInfo.this[string columnName]
53         {
54             get { return mBusinessRules.GetBrokenRules(columnName); }
55         }
56 
57         #endregion
58 
59     }

View Code

其中的BusinessRules对象mBusinessRules主要负责验证属性的正确性，这里只实现了一个粗糙版本的，没有抽象出验证规则Rule类。

将属性名和验证规则增加到mBusinessRules对象中，通过IDataErrorInfo的IDataErrorInfo.Error属性和IDataErrorInfo.this[string columnName]索引器验证每一列的正确性。Error是行头显示的提示信息。这里用到了lamda表达式和属性的遍历。

 1  public class BusinessRules
 2     {
 3         List<string> names = new List<string>();
 4         List<string> exp = new List<string>();
 5         public object info;//指向对象本身
 6 
 7         public List<string> CheckRules(string name)
 8         {
 9             return names;
10         }
11 
12         public string GetBrokenRules(string columnName)
13         {
14             for (int i = 0; i < names.Count; i++)
15             {
16                 List<object> list = new List<object>();
17                 if (info == null) return null;
18                 Type t = info.GetType();
19                 IEnumerable<System.Reflection.PropertyInfo> property = from pi in t.GetProperties() where pi.Name.ToLower() == columnName.ToLower() select pi;
20                 //IEnumerable<System.Reflection.PropertyInfo> property = t.GetProperties();
21                 foreach (PropertyInfo prpInfo in property)
22                 {
23                     string sProName = prpInfo.Name;
24                     object obj = prpInfo.GetValue(info, null);
25                     if (!Regex.IsMatch(obj.ToString(), exp[i]))
26                     {
27                         return "Error";
28                     }
29                 }
30             }
31             return "";
32         }
33 
34         public void AddRule(string ColName, string RegexExpress)
35         {
36             names.Add(ColName);
37             exp.Add(RegexExpress);
38         }
39     }

BusinessRules

接下来是数据实体Student，继承自BaseModel

 1  public class Student : BaseModel
 2     {
 3         public Student(string name)
 4         {
 5             mName = name;
 6         }
 7         private string mName;
 8         public string Name
 9         {
10             get
11             {
12                 return mName;
13             }
14             set
15             {
16                 if (mName != value)
17                 {
18                     mName = value;
19                     PropertyHasChanged("Name");
20                 }
21             }
22         }
23         public override void AddRule()
24         {
25             mBusinessRules.AddRule("Name", @"^-?\d+$");
26         }
27 
28     }

Student

最后是调用和效果：

1  private void button1_Click(object sender, EventArgs e)
2         {
3             BindingList<Student> list = new BindingList<Student>();
4             Student a = new Student("张三");
5             list.Add(a);
6             Student b = new Student("张三三");
7             list.Add(b);
8             gridControl1.DataSource = list;
9         }