下面的运行不对,该怎么改呢? int x ,y;
String kk = "sin(x)/x";
x = 2 ;
y = kk;//就是这怎么改?
Console.WriteLine ("{0}",y);
Console.ReadKey ;想编可可以画函数图像的小工具,可不知道怎么从文本框里获取输入的函数。
String kk = "sin(x)/x";
x = 2 ;
y = kk;//就是这怎么改?
Console.WriteLine ("{0}",y);
Console.ReadKey ;想编可可以画函数图像的小工具,可不知道怎么从文本框里获取输入的函数。
http://www.cnblogs.com/skyivben/archive/2005/11/01/266649.html
// 编译方法: csc ExpressionTest.cs Expression.cs
using System;
using Skyiv.Util;
namespace Skyiv.Test
{
class ExpressionTest
{
static void Main(string [] args)
{
try
{
if (args.Length > 0)
{
Console.WriteLine("f(x): {0}", args[0]);
Expression expression = new Expression(args[0]);
for (int i = 1; i < args.Length; i++)
{
double x = double.Parse(args[i]);
Console.WriteLine("f({0}) = {1}", x, expression.Compute(x));
}
}
else Console.WriteLine("Usage: ExpressionTest expression [ parameters ]");
}
catch (Exception ex)
{
Console.WriteLine("错误: " + ex.Message);
}
}
}
} // Expression.cs - 动态生成数学表达式并计算其值
// 表达式使用 C# 语法,可带一个的自变量(x)。
// 表达式的自变量和值均为(double)类型。
// 使用举例:
// Expression expression = new Expression("Math.Sin(x)");
// Console.WriteLine(expression.Compute(Math.PI / 2));
// expression = new Expression("double u = Math.PI - x;" +
// "double pi2 = Math.PI * Math.PI;" +
// "return 3 * x * x + Math.Log(u * u) / pi2 / pi2 + 1;");
// Console.WriteLine(expression.Compute(0));
using System;
using System.CodeDom.Compiler;
using Microsoft.CSharp;
using System.Reflection;
using System.Text;
namespace Skyiv.Util
{
sealed class Expression
{
object instance;
MethodInfo method;
public Expression(string expression)
{
if (expression.IndexOf("return") < 0) expression = "return " + expression + ";";
string className = "Expression";
string methodName = "Compute";
CompilerParameters p = new CompilerParameters();
p.GenerateInMemory = true;
CompilerResults cr = new CSharpCodeProvider().CompileAssemblyFromSource(p, string.
Format("using System;sealed class {0}{{public double {1}(double x){{{2}}}}}",
className, methodName, expression));
if(cr.Errors.Count > 0)
{
string msg = "Expression(\"" + expression + "\"): \n";
foreach (CompilerError err in cr.Errors) msg += err.ToString() + "\n";
throw new Exception(msg);
}
instance = cr.CompiledAssembly.CreateInstance(className);
method = instance.GetType().GetMethod(methodName);
}
public double Compute(double x)
{
return (double)method.Invoke(instance, new object [] { x });
}
}
}
using System.Collections.Generic;
using System.Text;
using Microsoft.CSharp;
using System.CodeDom.Compiler;
using System.CodeDom;
using System.IO;namespace ConsoleApplication51
{
class Program
{
static void Main(string[] args)
{
String kk = @"using System;"
+ "namespace XXX"
+ "{"
+ " public class YYY"
+ " {"
+ " public void OutputString()"
+ " {"
+ " Console.WriteLine((Math.Sin(10)/10).ToString());"
+ " }"
+ " }"
+ "}"; CSharpCodeProvider CCP = new CSharpCodeProvider();
ICodeCompiler CC = CCP.CreateCompiler(); CompilerParameters CP = new CompilerParameters();
CP.ReferencedAssemblies.Add("System.dll");
CP.GenerateInMemory = true; CodeSnippetCompileUnit CCU = new CodeSnippetCompileUnit(kk);
CompilerResults CR = CC.CompileAssemblyFromDom(CP, CCU); Type T = CR.CompiledAssembly.GetType("XXX.YYY");
Object Obj = CR.CompiledAssembly.CreateInstance("XXX.YYY");
T.GetMethod("OutputString").Invoke(Obj, null); Console.Read();
}
}
}
namespace不要也可以