注意：在{0}的冒号中之后的那个"CreditCardForm2“就是类的名字，不要写错，否就不行！还有runat=‘sever‘一定要写，其他的属性你可以随意加，但是要保证，那些你的家的属性是我们定义了的。例如你还可以加 CreditCardNo=‘信用卡号‘,等等。这样之后，我们的控件就更加的专业了！
整个代码如下：大家多多提意见，如果我讲不够好就说，我尽量讲的更加平实！
1usingSystem;
2usingSystem.Collections.Generic;
3usingSystem.Text;
4usingSystem.Web.UI;
5usingSystem.Web;
6usingSystem.ComponentModel;
7usingSystem.Web.UI.WebControls;
8
9namespaceCreditCardForm
10{
11 [DefaultProperty("CardholderNameText")]
12 [ToolboxData("<{0}:CreditCardForm2runat=‘server‘PaymentMethodText=‘支付方式‘></{0}:CreditCardForm2>")]
13 publicclassCreditCardForm2:Control
14 {
15 #region属性
16 privatestringpaymentMethod="支付方式";
17 privatestringcreditCardNo="信用卡号";
18 privatestringcardholderName="持卡人";
19 privatestringexpirati;
20 privatestringsubmitButt;
21
22 //以便以后二次开发所以用了virtual
23 //
24
25
26 [Browsable(true)]//在属性窗口中是否可见
27 [Category("Appearance")]//属性的分类，如，行为，外观，大家可以在属性窗口看见这样的分类
28 [DefaultValue("支付方式")]
29 [Description("支付方式")]//这些是显示在属性窗口底下的
30 publicvirtualstringPaymentMethodText
31 {
32 get
33 {
34 returnpaymentMethod;
35 }
36 set
37 {
38 paymentMethod=value;
39 }
40 }
41
42 [Browsable(true)]
43 [Category("Appearance")]
44 [DefaultValue("信用卡号")]
45 [Description("信用卡的号码")]
46 publicvirtualstringCreditCardNoText
47 {
48 get
49 {
50 returncreditCardNo;
51 }
52 set
53 {
54 creditCardNo=value;
55 }
56 }
57
58 [Browsable(true)]
59 [Category("Appearance")]
60 [DefaultValue("持卡人")]
61 [Description("持卡人的名字")]
62 publicvirtualstringCardholderNameText
63 {
64 get
65 {
66 returncardholderName;
67 }
68 set
69 {
70 cardholderName=value;
71 }
72 }
73
74 [Browsable(true)]
75 [Category("Appearance")]
76 [DefaultValue("过期时间")]
77 [Description("描述卡的过期时间")]
78 publicvirtualstringExpirationDateText
79 {
80 get
81 {
82 returnexpirationDate;
83 }
84 set
85 {
86 expirationDate=value;
87 }
88 }
89 [Browsable(true)]
90 [Description("按钮的文本")]
91 [Category("Appearance")]
92 [DefaultValue("提交")]
93 publicvirtualstringSubmitButtonText
94 {
95 get
96 {
97 returnsubmitButtonText;
98 }
99 set
100 {
101 submitButtonText=value;
102 }
103 }
104 #endregion
105 protectedoverridevoidRender(HtmlTextWriterwriter)
106 {
107 writer.Write("<tablestyle=‘width:287px;height:128px;border-width:0‘>");
108 writer.Write("<tr>");
109 writer.Write("<td>"+PaymentMethodText+"</td>");
110 writer.Write("<td>");
111 writer.Write("<selectname=‘paymentMethod‘id=‘paymentMethod‘style=‘width:100%‘>");
112 writer.Write("<optionvalue=‘0‘>Master</option>");
113 writer.Write("<optionvalue=‘1‘>Visa</option>");
114 writer.Write("</select>");
115 writer.Write("</td>");
116 writer.Write("</tr>");
117
118 writer.Write("<tr>");
119 writer.Write("<td>"+CreditCardNoText+"</td>");
120 writer.Write("<td><inputtype=‘text‘name=‘CreditCardNo‘id=‘CreditCardNo‘/></td>");
121 writer.Write("</tr>");
122
123 writer.Write("<tr>");
124 writer.Write("<td>"+CardholderNameText+"</td>");
125 writer.Write("<td><inputtype=‘text‘name=‘CardholderName‘id=‘CardholderName‘/></td>");
126 writer.Write("</tr>");
127
128 writer.Write("<tr>");
129 writer.Write("<td>"+ExpirationDateText+"</td>");
130 writer.Write("<td>");
131 writer.Write("<selectname=‘Month‘id=‘Month‘>");
132 for(intmonth=1;month<13;month++)
133 {
134 writer.Write("<opti>"+month.ToString()+"</option>");
135 }
136
137 writer.Write("</select>");
138
139 writer.Write(" ");
140
141 writer.Write("<selectname=‘Year‘id=‘Year‘>");
142 for(intyear=2008;year<2014;year++)
143 {
144 writer.Write("<opti>"+year.ToString()+"</option>");
145 }
146 writer.Write("</select>");
147 writer.Write("</td></tr>");
148
149 writer.Write("<tr>");
150 writer.Write("<tdalign=‘center‘colspan=‘2‘>");
151 writer.Write("<inputtype=‘submit‘value=‘"+SubmitButtonText+"‘/>");
152 writer.Write("</td></tr>");
153
154
155
156
157 }
158
159 }
160}
161
有问题。怎样改？
这样：
我们用.NET里面的专门用来生成这些html标记的一些方法和属性
1 writer.AddStyleAttribute(HtmlTextWriterStyle.Width, "287px");
2 writer.AddStyleAttribute(HtmlTextWriterStyle.Height, "128px");
3 writer.AddStyleAttribute(HtmlTextWriterStyle.BorderWidth, "0");
4 writer.AddAttribute(HtmlTextWriterAttribute.Id, "mytable");
5 writer.RenderBeginTag(HtmlTextWriterTag.Table);
这段代码和上端代码的最终的显示结果都是一样的（都生成相同的html标记）。也许大家会认为这段代码很多，难道写
这么多的代码就是好的吗，还不如之前的方便。但是，想想之前所说的问题，这段代码就解决了那些问题。
代码我来解释下：用AddStyleAttribute方法来添加CCS样式；AddStyleAttribute添加非CSS样式，如name，id等，
用RenderBeginTag来添加开始的标记。还有一点就是这些代码都是“反的”：先定义样式，属性，最后才定义我们要写的
个table标记。就是说，想给某个标记加属性，要先写属性，
样式的语句，在写这个标记。
1 writer.RenderBeginTag(HtmlTextWriterTag.Table);
2
看看上面的代码，显示的是个table标记，如果想显示tr？这样做：
1 writer.RenderBeginTag(HtmlTextWriterTag.Tr);
2
大家应该明白我的意思了吧：HtmlTextWriterTag接不同的属性，就显示不同的标记。
还有一点要特别的注意，有开始，就是结束。我们用了一个RenderBeginTag方法，就一定要有个RenderEndTag方法
与之对应。
看个例子：
1 writer.RenderBeginTag(HtmlTextWriterTag.Td);
2 writer.Write(PaymentMethodText);
3 writer.RenderEndTag();
大家懂了吧！
我把代码贴上，大家看看，有问题就说！
1 protected override void Render(HtmlTextWriter writer)
2 {
3 writer.AddStyleAttribute(HtmlTextWriterStyle.Width, "287px");
4 writer.AddStyleAttribute(HtmlTextWriterStyle.Height, "128px");
5 writer.AddStyleAttribute(HtmlTextWriterStyle.BorderWidth, "0");
6 writer.AddAttribute(HtmlTextWriterAttribute.Id, "mytable");
7 writer.RenderBeginTag(HtmlTextWriterTag.Table);
8
9 writer.RenderBeginTag(HtmlTextWriterTag.Tr);
10
11 writer.RenderBeginTag(HtmlTextWriterTag.Td);
12 writer.Write(PaymentMethodText);
13 writer.RenderEndTag();
14
15 writer.RenderBeginTag(HtmlTextWriterTag.Td);
16 writer.AddAttribute(HtmlTextWriterAttribute.Name, "PaymentMethod");
17 writer.AddAttribute(HtmlTextWriterAttribute.Id, "PaymentMethod");
18 writer.AddStyleAttribute(HtmlTextWriterStyle.Width, "100%");
19 writer.RenderBeginTag(HtmlTextWriterTag.Select);
20
21 writer.AddAttribute(HtmlTextWriterAttribute.Value, "0");
22 writer.RenderBeginTag(HtmlTextWriterTag.Option);
23 writer.Write("Master");
24 writer.RenderEndTag();
25
26 writer.AddAttribute(HtmlTextWriterAttribute.Value, "1");
27 writer.RenderBeginTag(HtmlTextWriterTag.Option);
28 writer.Write("Visa");
29 writer.RenderEndTag();
30
31 writer.RenderEndTag();
32 writer.RenderEndTag();
33 writer.RenderEndTag();
34
35 writer.RenderBeginTag(HtmlTextWriterTag.Tr);
36 writer.RenderBeginTag(HtmlTextWriterTag.Td);
37 writer.Write(CreditCardNoText);
38 writer.RenderEndTag();
39
40 writer.RenderBeginTag(HtmlTextWriterTag.Td);
41 writer.AddAttribute(HtmlTextWriterAttribute.Type, "text");
42 writer.AddAttribute(HtmlTextWriterAttribute.Name, "CreditCardNo");
43 writer.AddAttribute(HtmlTextWriterAttribute.Id, "CreditCardNo");
44 writer.RenderBeginTag(HtmlTextWriterTag.Input);
45 writer.RenderEndTag();
46 writer.RenderEndTag();
47 writer.RenderEndTag();
48
49 writer.RenderBeginTag(HtmlTextWriterTag.Tr);
50 writer.RenderBeginTag(HtmlTextWriterTag.Td);
51 writer.Write(CardholderNameText);
52 writer.RenderEndTag();
53
54 writer.RenderBeginTag(HtmlTextWriterTag.Td);
55 writer.AddAttribute(HtmlTextWriterAttribute.Type, "text");
56 writer.AddAttribute(HtmlTextWriterAttribute.Name, "CardholderName");
57 writer.AddAttribute(HtmlTextWriterAttribute.Id, "CardholderName");
58 writer.RenderBeginTag(HtmlTextWriterTag.Input);
59 writer.RenderEndTag();
60 writer.RenderEndTag();
61 writer.RenderEndTag();
62
63 writer.RenderBeginTag(HtmlTextWriterTag.Tr);
64 writer.RenderBeginTag(HtmlTextWriterTag.Td);
65 writer.Write(ExpirationDateText);
66 writer.RenderEndTag();
67
68 writer.RenderBeginTag(HtmlTextWriterTag.Td);
69 writer.AddAttribute(HtmlTextWriterAttribute.Name, "Month");
70 writer.AddAttribute(HtmlTextWriterAttribute.Id, "Month");
71 writer.RenderBeginTag(HtmlTextWriterTag.Select);
72 for (int month = 1; month < 13; month++)
73 {
74 writer.AddAttribute(HtmlTextWriterAttribute.Value, month.ToString());
75 writer.RenderBeginTag(HtmlTextWriterTag.Option);
76 writer.Write(month.ToString());
77 writer.RenderEndTag();
78 }
79
80 writer.RenderEndTag();
81
82 writer.Write(" ");
83
84 writer.AddAttribute(HtmlTextWriterAttribute.Name, "Year");
85 writer.AddAttribute(HtmlTextWriterAttribute.Id, "Year");
86 writer.RenderBeginTag(HtmlTextWriterTag.Select);
87
88 for (int year =2008; year < 2015; year++)
89 {
90 writer.AddAttribute(HtmlTextWriterAttribute.Value, year.ToString());
91 writer.RenderBeginTag(HtmlTextWriterTag.Option);
92 writer.Write(year.ToString());
93 writer.RenderEndTag();
94 }
95
96 writer.RenderEndTag();
97
98 writer.RenderEndTag();
99 writer.RenderEndTag();
100
101
102 writer.RenderBeginTag(HtmlTextWriterTag.Tr);
103 writer.AddAttribute(HtmlTextWriterAttribute.Colspan, "2");
104 writer.AddAttribute(HtmlTextWriterAttribute.Align, "center");
105 writer.RenderBeginTag(HtmlTextWriterTag.Td);
106 writer.AddAttribute(HtmlTextWriterAttribute.Type, "submit");
107 writer.AddAttribute(HtmlTextWriterAttribute.Value, SubmitButtonText);
108 writer.RenderBeginTag(HtmlTextWriterTag.Input);
109 writer.RenderEndTag();
110 writer.RenderEndTag();
111 writer.RenderEndTag();
112
113 //table的结束标记
114 writer.RenderEndTag();
115
116
117
118
119 }
下面开始说说。状态的管理，即ViewState; 之前的控件还有一个问题：
如下：
我们在页面后面写代码：
1protectedvoidPage_Load(objectsender,EventArgse)
2 {
3 if(!this.IsPostBack)
4 {
5 CreditCardForm2_1.PaymentMethodText="我的支付方式";
6 CreditCardForm2_1.CardholderNameText="小洋";
7 }
8 }
运行页面看见：
但是当你点击”提交“按钮，页面马上就变为了如下：
变回来了！！！！？？？？？
这里就要讲讲ASP.NET的页面保存值的方式：因为现在的ASP.NET网站是基于http这种无状态协议的。大家应该都懂。
在ASP.NET的我们提交的一个页面，虽然看起来是一样的，但是他们本质上已经不是同一个页面了。而是我们现在看见的页
面获取了之前提交的那个页面的一些状态值。关于这点，到第四章详细讲述”页面的生命周期“中讲。
所有我们就要用个ViewState来保存页面回传的值。这里我不想讲很多的理论东西，大家先看看现在的问题怎样解决：
public override string PaymentMethodText
{
get
{
return ViewState["PaymentMethodText"] != null ? (string)ViewState["PaymentMethodText"] : "支付方式";
}
set
{
ViewState["PaymentMethodText"] = value;
}
}
因为我们继承于CreditCardForm2，大家看看我们在CreditCardForm2中写的：
1
2 [Browsable (true )]//在属性窗口中是否可见
3 [Category ("Appearance")]//属性的分类，如，行为，外观，大家可以在属性窗口看见这样的分类
4 [DefaultValue ("支付方式")]
5 [Description ("支付方式")]//这些是显示在属性窗口底下的
6
7 //virtual 方便以后二次开发
8 public virtual string PaymentMethodText
9 {
10 get
11 {
12 return paymentMethod;
13 }
14 set
15 {
16 paymentMethod = value;
17 }
18 }
19
注意：Virtual。
这样之后，我们的控件就完成了。完整的代码如下：希望大家支持！
1using System;
2using System.Collections.Generic;
3using System.Text;
4using System.Web;
5using System.Web.UI;
6using System.Web.UI.WebControls;
7
8namespace CreditCardForm
9{
10 public class CreditCardForm3:CreditCardForm2
11 {
12 public override string PaymentMethodText
13 {
14 get
15 {
16 return ViewState["PaymentMethodText"] != null ? (string)ViewState["PaymentMethodText"] : "支付方式";
17 }
18 set
19 {
20 ViewState["PaymentMethodText"] = value;
21 }
22 }
23
24 public override string CreditCardNoText
25 {
26 get
27 {
28 return ViewState["CreditCardNoText"] != null ? (string)ViewState["CreditCardNoText"] : "信用卡号";
29 }
30 set
31 {
32 ViewState["CreditCardNoText"] = value;
33 }
34 }
35
36 public override string CardholderNameText
37 {
38 get
39 {
40 return ViewState["CardholderNameText"] != null ? (string)ViewState["CardholderNameText"] : "持卡人";
41 }
42 set
43 {
44 ViewState["CardholderNameText"] = value;
45 }
46 }
47
48 public override string ExpirationDateText
49 {
50 get
51 {
52 return ViewState["ExpirationDateText"] != null ? (string)ViewState["ExpirationDateText"] : "过期时间";
53 }
54 set
55 {
56 ViewState["ExpirationDateText"] = value;
57 }
58 }
59
60 public override string SubmitButtonText
61 {
62 get
63 {
64 return ViewState["SubmitButtonText"] != null ? (string)ViewState["SubmitButtonText"] : "提交";
65 }
66 set
67 {
68 ViewState["SubmitButtonText"] = value;
69 }
70 }
71 protected override void Render(HtmlTextWriter writer)
72 {
73 writer.AddStyleAttribute(HtmlTextWriterStyle.Width, "287px");
74 writer.AddStyleAttribute(HtmlTextWriterStyle.Height, "128px");
75 writer.AddStyleAttribute(HtmlTextWriterStyle.BorderWidth, "0");
76 writer.AddAttribute(HtmlTextWriterAttribute.Id, "mytable");
77 writer.RenderBeginTag(HtmlTextWriterTag.Table);
78
79 writer.RenderBeginTag(HtmlTextWriterTag.Tr);
80
81 writer.RenderBeginTag(HtmlTextWriterTag.Td);
82 writer.Write(PaymentMethodText);
83 writer.RenderEndTag();
84
85 writer.RenderBeginTag(HtmlTextWriterTag.Td);
86 writer.AddAttribute(HtmlTextWriterAttribute.Name, "PaymentMethod");
87 writer.AddAttribute(HtmlTextWriterAttribute.Id, "PaymentMethod");
88 writer.AddStyleAttribute(HtmlTextWriterStyle.Width, "100%");
89 writer.RenderBeginTag(HtmlTextWriterTag.Select);
90
91 writer.AddAttribute(HtmlTextWriterAttribute.Value, "0");
92 writer.RenderBeginTag(HtmlTextWriterTag.Option);
93 writer.Write("Master");
94 writer.RenderEndTag();
95
96 writer.AddAttribute(HtmlTextWriterAttribute.Value, "1");
97 writer.RenderBeginTag(HtmlTextWriterTag.Option);
98 writer.Write("Visa");
99 writer.RenderEndTag();
100
101 writer.RenderEndTag();
102 writer.RenderEndTag();
103 writer.RenderEndTag();
104
105 writer.RenderBeginTag(HtmlTextWriterTag.Tr);
106 writer.RenderBeginTag(HtmlTextWriterTag.Td);
107 writer.Write(CreditCardNoText);
108 writer.RenderEndTag();
109
110 writer.RenderBeginTag(HtmlTextWriterTag.Td);
111 writer.AddAttribute(HtmlTextWriterAttribute.Type, "text");
112 writer.AddAttribute(HtmlTextWriterAttribute.Name, "CreditCardNo");
113 writer.AddAttribute(HtmlTextWriterAttribute.Id, "CreditCardNo");
114 writer.RenderBeginTag(HtmlTextWriterTag.Input);
115 writer.RenderEndTag();
116 writer.RenderEndTag();
117 writer.RenderEndTag();
118
119 writer.RenderBeginTag(HtmlTextWriterTag.Tr);
120 writer.RenderBeginTag(HtmlTextWriterTag.Td);
121 writer.Write(CardholderNameText);
122 writer.RenderEndTag();
123
124 writer.RenderBeginTag(HtmlTextWriterTag.Td);
125 writer.AddAttribute(HtmlTextWriterAttribute.Type, "text");
126 writer.AddAttribute(HtmlTextWriterAttribute.Name, "CardholderName");
127 writer.AddAttribute(HtmlTextWriterAttribute.Id, "CardholderName");
128 writer.RenderBeginTag(HtmlTextWriterTag.Input);
129 writer.RenderEndTag();
130 writer.RenderEndTag();
131 writer.RenderEndTag();
132
133 writer.RenderBeginTag(HtmlTextWriterTag.Tr);
134 writer.RenderBeginTag(HtmlTextWriterTag.Td);
135 writer.Write(ExpirationDateText);
136 writer.RenderEndTag();
137
138 writer.RenderBeginTag(HtmlTextWriterTag.Td);
139 writer.AddAttribute(HtmlTextWriterAttribute.Name, "Month");
140 writer.AddAttribute(HtmlTextWriterAttribute.Id, "Month");
141 writer.RenderBeginTag(HtmlTextWriterTag.Select);
142 for (int month = 1; month < 13; month++)
143 {
144 writer.AddAttribute(HtmlTextWriterAttribute.Value, month.ToString());
145 writer.RenderBeginTag(HtmlTextWriterTag.Option);
146 writer.Write(month.ToString());
147 writer.RenderEndTag();
148 }
149
150 writer.RenderEndTag();
151
152 writer.Write(" ");
153
154 writer.AddAttribute(HtmlTextWriterAttribute.Name, "Year");
155 writer.AddAttribute(HtmlTextWriterAttribute.Id, "Year");
156 writer.RenderBeginTag(HtmlTextWriterTag.Select);
157
158 for (int year =2008; year < 2015; year++)
159 {
160 writer.AddAttribute(HtmlTextWriterAttribute.Value, year.ToString());
161 writer.RenderBeginTag(HtmlTextWriterTag.Option);
162 writer.Write(year.ToString());
163 writer.RenderEndTag();
164 }
165
166 writer.RenderEndTag();
167
168 writer.RenderEndTag();
169 writer.RenderEndTag();
170
171
172 writer.RenderBeginTag(HtmlTextWriterTag.Tr);
173 writer.AddAttribute(HtmlTextWriterAttribute.Colspan, "2");
174 writer.AddAttribute(HtmlTextWriterAttribute.Align, "center");
175 writer.RenderBeginTag(HtmlTextWriterTag.Td);
176 writer.AddAttribute(HtmlTextWriterAttribute.Type, "submit");
177 writer.AddAttribute(HtmlTextWriterAttribute.Value, SubmitButtonText);
178 writer.RenderBeginTag(HtmlTextWriterTag.Input);
179 writer.RenderEndTag();
180 writer.RenderEndTag();
181 writer.RenderEndTag();
182
183 writer.RenderEndTag();
184
185
186
187
188 }
189 }
190}
191
