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  • c# 将字符串转换为逻辑表达式(字符串转换布尔)

    比如:string str="6>5";

    要的效果是:bool result=6>5

    方案一:

    命名空间:System.Data;

     DataTable dt = new DataTable();

     bool result= (bool)dt.Compute("","");dt.Compute(str, "");

    方案二:

    动态表达式:

     1 public class Expression
     2     {
     3         object instance;
     4         MethodInfo method;
     5         /// <summary>
     6         /// 表达试运算
     7         /// </summary>
     8         /// <param name="expression">表达试</param>
     9         public Expression(string expression)
    10         {
    11   if (expression.IndexOf("return") < 0) expression = "return " + expression + ";";
    12             string className = "Expression";
    13             string methodName = "Compute";
    14             CompilerParameters p = new CompilerParameters();
    15             p.GenerateInMemory = true;
    16             CompilerResults cr = new CSharpCodeProvider().CompileAssemblyFromSource(p, string.
    17               Format("using System;sealed class {0}{{public bool {1}(bool x){{{2}}}}}",
    18               className, methodName, expression));
    19             if (cr.Errors.Count > 0)
    20             {
    21                 string msg = "Expression("" + expression + ""): 
    ";
    22                 foreach (CompilerError err in cr.Errors) msg += err.ToString() + "
    ";
    23                 throw new Exception(msg);
    24             }
    25             instance = cr.CompiledAssembly.CreateInstance(className);
    26             method = instance.GetType().GetMethod(methodName);
    27  }
    28  /// <summary>
    29         /// 处理数据
    30         /// </summary>
    31         /// <param name="x"></param>
    32         /// <returns>返回计算值</returns>
    33         public bool Compute(bool x)
    34         {
    35             return (bool)method.Invoke(instance, new object[] { x });
    36         }
    View Code

     方案三:

    欢迎各位各位提供方案,谢谢!

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  • 原文地址:https://www.cnblogs.com/zlp520/p/3867740.html
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