asp.net C#下如何获取动态代码的值代码

下面是调用(注意调用时特殊字符的转义)

1 color coor = csharpcodevaluehelper<color>.getcodevalue("color.fromargb(100,100,100)");
2
3
4 image img = csharpcodevaluehelper<image>.getcodevalue("image.fromfile("c:\tu.jpg")");

代码如下
1 usingmicrosoft.csharp;
2 usingsystem.reflection;
3 using system.codedom.compiler;
4
5 public static class csharpcodevaluehelper<t>
6 {
7 /// <summary>
8 /// 编译器实例
9 /// </summary>
10 private static csharpcodeprovider csharpcodeprovider { get; set; }
11
12 /// <summary>
13 /// 编译器参数
14 /// </summary>
15 private static compilerparameters compilerparameters { get; set; }
16
17 /// <summary>
18 /// 构造函数
19 /// </summary>
20 static csharpcodevaluehelper()
21 {
22 csharpcodeprovider = new csharpcodeprovider();
23
24 compilerparameters = new compilerparameters();
25 compilerparameters.referencedassemblies.add("system.dll");
26 compilerparameters.referencedassemblies.add("system.data.dll");
27 compilerparameters.referencedassemblies.add("system.deployment.dll");
28 compilerparameters.referencedassemblies.add("system.drawing.dll");
29 compilerparameters.referencedassemblies.add("system.windows.forms.dll");
30 compilerparameters.referencedassemblies.add("system.xml.dll");
31 compilerparameters.generateexecutable = false;
32 compilerparameters.generateinmemory = true;
33 }
34
35 /// <summary>
36 /// 获取代码的值
37 /// </summary>
38 /// <param name="csharpcode">csharpcode代码</param>
39 /// <returns>动态csharpcode代码的值</returns>
40 public static t getcodevalue(string csharpcode)
41 {
42 compilerresults compilerresults = csharpcodeprovider.compileassemblyfromsource(compilerparameters, createcode(csharpcode));
43
44 if (compilerresults.errors.haserrors)
45 {
46 string errorstring = string.empty;
47 errorstring += "编译错误：n";
48 foreach (compilererror err in compilerresults.errors)
49 {
50 errorstring += err.errortext + "n";
51 }
52 throw new exception(errorstring);
53 }
54 else
55 {
56 // 通过反射，调用动态类dynamicclass实例
57 assembly assembly = compilerresults.compiledassembly;
58 object dynamicclass = assembly.createinstance("dynamicnamespace.dynamicclass");
59 methodinfo methodinfo = dynamicclass.gettype().getmethod("getvalue");
60
61 return (t)methodinfo.invoke(dynamicclass, null);
62 }
63 }
64
65 /// <summary>
66 /// 创建代码
67 /// </summary>
68 /// <param name="csharpcode">csharpcode代码</param>
69 /// <returns>创建完成的代码www.3ppt.com</returns>
70 private static string createcode(string csharpcode)
71 {
72 stringbuilder strbuilder = new stringbuilder();
73 strbuilder.appendline("using system;");
74 strbuilder.appendline("using system.collections.generic;");
75 strbuilder.appendline("using system.componentmodel;");
76 strbuilder.appendline("using system.data;");
77 strbuilder.appendline("using system.drawing;");
78 strbuilder.appendline("using system.text;");
79 strbuilder.appendline("using system.windows.forms;");
80
81 strbuilder.appendline("namespace dynamicnamespace");
82 strbuilder.appendline("{");
83 strbuilder.appendline(" public class dynamicclass");
84 strbuilder.appendline(" {");
85 strbuilder.appendline(" public object getvalue()");
86 strbuilder.appendline(" {");
87 strbuilder.appendline(" return " + csharpcode + ";");
88 strbuilder.appendline(" }");
89 strbuilder.appendline(" }");
90 strbuilder.appendline("}");
91
92 string code = strbuilder.tostring();
93 return code;
94 }
95 }