C# 带有DynamicExpression.ParseLambda的谓词

我正在构建一个动态过滤列表。我将从UI收到一个谓词（如“Name==”Australia“”），代码将过滤列表。对于“==”操作符来说，它工作得很好。

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但是，我正在努力解决以下条件，不确定UI将如何在谓词中传递以下条件

包含

开始于

以

不等于

大于

少于

中间

我在下面复制了我的源代码。在此帮忙将不胜感激

class Program
    {
        static void Main(string[] args)
        {
            var lst = new List<Myclass>();

            lst.Add(new Myclass { Name = "Australia", Id = 1, Dt = System.DateTime.Now.AddDays(10) });
            lst.Add(new Myclass { Name = "USA", Id = 2, Dt = System.DateTime.Now.AddDays(5) });
            lst.Add(new Myclass { Name = "India", Id = 3, Dt = System.DateTime.Now});

            var result = lst.AsQueryable().Where(DynamicExpression.ParseLambda<Myclass, bool>("Name == \"Australia\""));
            var r = result.ToList();

        }
    }

    public class Myclass
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public DateTime Dt { get; set; }
    }

类程序
{
静态void Main（字符串[]参数）
{
var lst=新列表（）；
lst.Add（newmyclass{Name=“Australia”，Id=1，Dt=System.DateTime.Now.AddDays（10）}）；
lst.Add（newmyclass{Name=“USA”，Id=2，Dt=System.DateTime.Now.AddDays（5）}）；
添加（新的Myclass{Name=“India”，Id=3，Dt=System.DateTime.Now}）；
var result=lst.AsQueryable（）；
var r=result.ToList（）；
}
}
公共类Myclass
{
公共int Id{get；set；}
公共字符串名称{get；set；}
公共日期时间Dt{get；set；}
}

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我想我找到了我需要的谓词

Text Field Equal To = string exp = "(Name =\"India\")";
Text Field NOT Equal To = string exp = "(Name !=\"India\")";
Text Field Contains = string exp = "(Name.Contains (\"Ind\"))";
Text Field Starts With = string exp = "(Name.StartsWith (\"Ind\"))";
Text Field Ends With = string exp = "(Name.EndsWith (\"a\"))";

Number Field Equal to = string exp = "(Id = 1)";
Number Field Between with multiple conditions = string exp = "(Id > 1 AND Id <= 3) OR Id =3";
Number Field Between and greater than equal to = string exp = "(Id > 1 AND Id >= 3)";

Date Field Between  = string exp = "(Dt > Convert.ToDateTime(\"2/5/2021 4:46:04 AM\") AND Dt >= Convert.ToDateTime(\"2/3/2021 4:46:04 AM\"))";

Text Field Equal To = string exp = "(Name =\"India\")";
Text Field NOT Equal To = string exp = "(Name !=\"India\")";
Text Field Contains = string exp = "(Name.Contains (\"Ind\"))";
Text Field Starts With = string exp = "(Name.StartsWith (\"Ind\"))";
Text Field Ends With = string exp = "(Name.EndsWith (\"a\"))";

Number Field Equal to = string exp = "(Id = 1)";
Number Field Between with multiple conditions = string exp = "(Id > 1 AND Id <= 3) OR Id =3";
Number Field Between and greater than equal to = string exp = "(Id > 1 AND Id >= 3)";

Date Field Between  = string exp = "(Dt > Convert.ToDateTime(\"2/5/2021 4:46:04 AM\") AND Dt >= Convert.ToDateTime(\"2/3/2021 4:46:04 AM\"))";

文本字段等于=string exp=“（Name=\'India\””；
文本字段不等于=string exp=“（Name！=“India\”）；
文本字段Contains=string exp=“（Name.Contains（\“Ind\”）”）；
文本字段以=string exp=“（Name.StartsWith（\“Ind\”）开头）；
文本字段以=string exp=“（Name.EndsWith（\'a\”）结尾；
数字字段等于=字符串exp=“（Id=1）”；
具有多个条件的数字字段=字符串exp=“（Id>1且Id 1且Id>=3）”；
日期字段介于=string exp=“（Dt>Convert.ToDateTime（\'2/5/2021 4:46:04 AM\”）和Dt>=Convert.ToDateTime（\'2/3/2021 4:46:04 AM\”）之间）；

我想我找到了我需要的谓词

Text Field Equal To = string exp = "(Name =\"India\")";
Text Field NOT Equal To = string exp = "(Name !=\"India\")";
Text Field Contains = string exp = "(Name.Contains (\"Ind\"))";
Text Field Starts With = string exp = "(Name.StartsWith (\"Ind\"))";
Text Field Ends With = string exp = "(Name.EndsWith (\"a\"))";

Number Field Equal to = string exp = "(Id = 1)";
Number Field Between with multiple conditions = string exp = "(Id > 1 AND Id <= 3) OR Id =3";
Number Field Between and greater than equal to = string exp = "(Id > 1 AND Id >= 3)";

Date Field Between  = string exp = "(Dt > Convert.ToDateTime(\"2/5/2021 4:46:04 AM\") AND Dt >= Convert.ToDateTime(\"2/3/2021 4:46:04 AM\"))";

Text Field Equal To = string exp = "(Name =\"India\")";
Text Field NOT Equal To = string exp = "(Name !=\"India\")";
Text Field Contains = string exp = "(Name.Contains (\"Ind\"))";
Text Field Starts With = string exp = "(Name.StartsWith (\"Ind\"))";
Text Field Ends With = string exp = "(Name.EndsWith (\"a\"))";

Number Field Equal to = string exp = "(Id = 1)";
Number Field Between with multiple conditions = string exp = "(Id > 1 AND Id <= 3) OR Id =3";
Number Field Between and greater than equal to = string exp = "(Id > 1 AND Id >= 3)";

Date Field Between  = string exp = "(Dt > Convert.ToDateTime(\"2/5/2021 4:46:04 AM\") AND Dt >= Convert.ToDateTime(\"2/3/2021 4:46:04 AM\"))";

文本字段等于=string exp=“（Name=\'India\””；
文本字段不等于=string exp=“（Name！=“India\”）；
文本字段Contains=string exp=“（Name.Contains（\“Ind\”）”）；
文本字段以=string exp=“（Name.StartsWith（\“Ind\”）开头）；
文本字段以=string exp=“（Name.EndsWith（\'a\”）结尾；
数字字段等于=字符串exp=“（Id=1）”；
具有多个条件的数字字段=字符串exp=“（Id>1且Id 1且Id>=3）”；
日期字段介于=string exp=“（Dt>Convert.ToDateTime（\'2/5/2021 4:46:04 AM\”）和Dt>=Convert.ToDateTime（\'2/3/2021 4:46:04 AM\”）之间）；

“然而我在以下条件下挣扎”-您尝试了什么，发生了什么？我尝试了谓词“Name Like\%Australia%\”，但它引发了异常。我不确定如何为Like编写谓词。它引发了什么异常？异常类型和消息是什么？当我找到问题的解决方案时，可以结束此问题。我已经用答案更新了我的问题。@Machindra请随意将其作为下面的实际答案发布-回答您自己的问题也意味着您可以接受答案（您得到的回答+该问题不再列为“未回答”）