定制控件的属性,属性转换器及使用

先定义要展示的属性:

 1using System;
 2using System.ComponentModel;
 3
 4namespace WroxControls
 5{
 6    /**//// <summary>
 7    /// Dog 的摘要说明。
 8    /// </summary>
 9    /// 
10    public enum eBreed
11    {        Dalmation,Labrador,GoldenRetrieve,Mutt,BlackLabradorRetriever
12    }
13
14    [TypeConverter(typeof(DogConverter))]
15    public struct Dog
16    {            
17        private string _Name;
18        private eBreed _Breed;
19        private int _Age;
20        
21        public Dog(string name,eBreed breed,int age)
22        {
23            _Name = name;
24            _Breed = breed;
25            _Age = age;
26        }
27
28        public string Name
29        {
30            get { return _Name; }
31            set { _Name = value;}
32        }
33        public eBreed Breed
34        {
35            get { return _Breed; }
36            set { _Breed = value;}
37        }
38        public int Age
39        {
40            get { return _Age; }
41            set { _Age = value;}
42        }
43
44    }
45}
46

再定义转换函数:

 1using System;
 2using System.Reflection;
 3using System.Web;
 4using System.Web.UI.WebControls;
 5using System.ComponentModel;
 6using System.ComponentModel.Design.Serialization;
 7
 8namespace WroxControls
 9{
10    /**//// <summary>
11    /// DogConverter 的摘要说明。
12    /// </summary>
13    public class DogConverter:ExpandableObjectConverter
14    {
15        public DogConverter()
16        {
17            //
18            // TODO: 在此处添加构造函数逻辑
19            //
20        }
21        public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
22        {
23            if( sourceType == typeof(string) )
24                return true;
25            else
26                return base.CanConvertFrom (context, sourceType);
27        }
28        public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
29        {
30            if(destinationType == typeof(InstanceDescriptor) || destinationType == typeof(string))
31                return true;
32            else
33                return base.CanConvertTo (context, destinationType);
34        }
35        public override object ConvertFrom(ITypeDescriptorContext context, System.Globalization.CultureInfo culture, object value)
36        {
37            string sValue = value as string;
38            if(sValue != null)
39            {
40                string[] v = sValue.Split(new char[]{','});
41                return new Dog(v[0],(eBreed)Enum.Parse(typeof(eBreed),v[1]),Int32.Parse(v[2]));
42            }
43            else
44                return base.ConvertFrom (context, culture, value);
45        }
46        public override object ConvertTo(ITypeDescriptorContext context, System.Globalization.CultureInfo culture, object value, Type destinationType)
47        {
48            Dog dg = (Dog)value;
49            if(destinationType == typeof(InstanceDescriptor))
50            {
51                Type[] parms = new Type[]{ typeof(string),typeof(eBreed),typeof(int)};
52                object[] vals = new object[]{dg.Name,dg.Breed,dg.Age};
53                return new InstanceDescriptor(typeof(Dog).GetConstructor(parms),vals);
54                
55            }
56            else if( destinationType == typeof(string))
57            {
58                return string.Format("{0},{1},{2}",dg.Name,dg.Breed,dg.Age);
59            }
60            return base.ConvertTo (context, culture, value, destinationType);
61        }
62
63    }
64}
65

最后定义控件并引用:

 1using System;
 2using System.Web;
 3using System.Web.UI;
 4using System.ComponentModel;
 5
 6namespace WroxControls
 7{
 8    /**//// <summary>
 9    /// DogControl 的摘要说明。
10    /// </summary>
11    public class DogControl:System.Web.UI.Control
12    {
13        public DogControl()
14        {
15            //
16            // TODO: 在此处添加构造函数逻辑
17            //
18        }
19        private Dog _DogAttribute;
20        public Dog DogAttribute
21        {
22            get
23            {
24                return _DogAttribute;
25            }
26            set
27            {
28                _DogAttribute = value;
29            }
30        }
31    }
32}