C# 在变量中存储数学运算符

我正在用C#MVVM创建一个应用程序。我有一个简单的问题。是否有可能将数学运算符存储在变量中？我有这样一个代码：

public ICollectionView FilteredCollection
            {
                get
                {
                    return filteredCollection;
                }
                set
                {
                    filteredCollection = value;
                    OnPropertyChanged("FilteredCollection");
                }
            }



 FilteredCollection.Filter = x => (
                    (string.IsNullOrEmpty(DynamicSearchEmployeeName) || ((Employee)x).EmployeeName.Contains(DynamicSearchEmployeeName))
                    && (DynamicSearchEmployeeID == null || ((Employee)x).EmployeeID == DynamicSearchEmployeeID)
                    && (string.IsNullOrEmpty(DynamicSearchEmployeeSalary) || ((Employee)x).EmployeeSalary == Convert.ToInt32(DynamicSearchEmployeeSalary))
                    && (string.IsNullOrEmpty(DynamicSearchEmployeeDesigner) || ((Employee)x).EmployeeName.Contains(DynamicSearchEmployeeDesigner))
                    && (string.IsNullOrEmpty(DynamicSearchEmployeeEmailID) || ((Employee)x).EmployeeName.Contains(DynamicSearchEmployeeEmailID))
                    );

我想要达到的目标： 在第四行（DynamicSearchEmployeeSalary）中，数学运算符应取决于以下条件：

if (IsPressedEqual == true)
VARIABLE = "=="
if (IsPressedLess == true)
VARIABLE = "<"
if (IsPressedGreater == true)
VARIABLE = ">"
if (IsPressedLess == true && IsPressedEqual == true)
VARIABLE = "<="
if (IsPressedGreater == true && IsPressedEqual == true)
VARIABLE = ">="

---

我已经做了一个简单的基于规则的引擎。。。我想这会对你的问题有所帮助

请在此处以nuget软件包的形式查找：

您可以创建如下规则：

var rule = RuleEngine.CreateRule<Employee>()
                     .If<Employee>(e => e.EmployeeSalary).GreaterThan(DynamicSearchEmployeeSalary)
                     .Validate();

FilteredCollection.Filter = x => (
                    (string.IsNullOrEmpty(DynamicSearchEmployeeName) || ((Employee)x).EmployeeName.Contains(DynamicSearchEmployeeName))
                    && (DynamicSearchEmployeeID == null || ((Employee)x).EmployeeID == DynamicSearchEmployeeID)
                    && (string.IsNullOrEmpty(DynamicSearchEmployeeSalary) || rule.Match((Employee)x).IsMatch)
                    && (string.IsNullOrEmpty(DynamicSearchEmployeeDesigner) || ((Employee)x).EmployeeName.Contains(DynamicSearchEmployeeDesigner))
                    && (string.IsNullOrEmpty(DynamicSearchEmployeeEmailID) || ((Employee)x).EmployeeName.Contains(DynamicSearchEmployeeEmailID))

var rule=RuleEngine.CreateRule（）
.If（e=>e.EmployeeSalary）.大于（DynamicSearchEmployeeSalary）
.Validate（）；
FilteredCollection.Filter=x=>(
（string.IsNullOrEmpty（DynamicSearchEmployeeName）| |（（Employee）x）.EmployeeName.Contains（DynamicSearchEmployeeName））
&&（DynamicSearchEmployeeID==null | |（（Employee）x）.EmployeeID==DynamicSearchEmployeeID）
&&（string.IsNullOrEmpty（DynamicSearchEmployeeSalary）| | rule.Match（（Employee）x.IsMatch）
&&（string.IsNullOrEmpty（DynamicSearchEmployeeDesigner）| |（（Employee）x）.EmployeeName.Contains（DynamicSearchEmployeeDesigner））
&&（string.IsNullOrEmpty（DynamicSearchEmployeeEmailID）| |（（Employee）x）.EmployeeName.Contains（DynamicSearchEmployeeEmailID））

---

请随意添加任何注释或对包作出贡献

您打算如何在查询中使用它？什么是

FilteredCollection

？您能否显示在理想情况下运算符的使用位置？您不能单独存储运算符，但：您可以组合查询-用于LINQ和to对象（

IEnumerable

）和LINQ to-（随便什么）（

IQueryable

）-您可以非常灵活地构建表达式树（通过使用典型编译器解释结构的替代构造语法）.那么：您将如何使用它？这对任何答案都会产生巨大影响。我认为您不会自行存储变量，但您确实可以存储…第二个Patrick提出的问题…这些查询将在何处运行？本地作为LINQ2对象，还是将它们转换为Linq2EF/Linq2Sql？我编辑了我的问题。

var rule = RuleEngine.CreateRule<Employee>()
                     .If<Employee>(e => e.EmployeeSalary).GreaterThan(DynamicSearchEmployeeSalary)
                     .Validate();

FilteredCollection.Filter = x => (
                    (string.IsNullOrEmpty(DynamicSearchEmployeeName) || ((Employee)x).EmployeeName.Contains(DynamicSearchEmployeeName))
                    && (DynamicSearchEmployeeID == null || ((Employee)x).EmployeeID == DynamicSearchEmployeeID)
                    && (string.IsNullOrEmpty(DynamicSearchEmployeeSalary) || rule.Match((Employee)x).IsMatch)
                    && (string.IsNullOrEmpty(DynamicSearchEmployeeDesigner) || ((Employee)x).EmployeeName.Contains(DynamicSearchEmployeeDesigner))
                    && (string.IsNullOrEmpty(DynamicSearchEmployeeEmailID) || ((Employee)x).EmployeeName.Contains(DynamicSearchEmployeeEmailID))