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How to understand the simple reflection class library NMSReflector? in view of this problem, this article introduces the corresponding analysis and solution in detail, hoping to help more partners who want to solve this problem to find a more simple and feasible method.

Background introduction

I've seen some code before, which is simply reading SqlReader and assigning values to Model. It's not that I don't agree with this practice, but I just see that a lot of assignment is really a waste of time and energy, especially for some old projects. What I see is good, there are only more than 60 fields and no other ORM is needed. If changes are involved, it may not only be eyesight for the maintenance staff, but also. Manual work. In addition, there is the operation of the table, because I have written similar items before, the column name corresponds to the Model attribute name, one is not bad, and I vaguely feel that they should be connected, so I wonder if I can simplify its operation as much as possible? Maybe it's because you've done so few projects that you can only think of reflection, but the performance of reflection is well known. a large number of reflection assignments can be so slow that you blink a few times, but I think it's a disaster for the program. Therefore, combined with the reflection method to write this library, if it can bring you some convenience in the project, I will be satisfied.

Case 1:

Public class Student: INMSReflector {

Public string Name

Public string Description {get; set;}

Public static string StaticField

Public static string StaticProperty {get; set;}

}

Reference steps:

Step1: reference class library.

Step2: using NMSReflector.

Step3: implement the INMSReflector interface for your class; (of course, if you find it troublesome, you can change the source code, in ModelOperator.cs).

Step4: use the Create method to create a cache. (all classes that search for entry assemblies are scanned)

Because the object type is extended in the class library, the object instance can call the extension method.

1. EmitSet (string propertyName,object value) assigns a value to the field or property of the object

2. EmitGet (string propertyName) gets a field or attribute value of an object

Usage:

ModelOperator.Create ()

Student t = new Student ()

/ / normal field

T.Name = "Xiao Ming"

T.EmitSet ("Name", "the red scarf on Xiaoming's chest is getting brighter!")

Console.WriteLine (t.Name)

Console.WriteLine (t.EmitGet ("Name"))

/ / General attribute

T.EmitSet ("Description", "he loves Xiao Gang")

Console.WriteLine (t.Description)

Console.WriteLine (t.EmitGet ("Description"))

/ / static field

T.EmitSet ("StaticFiled", "he is next to Xiao Gang")

Console.WriteLine (Student.StaticField)

Console.WriteLine (t.EmitGet ("StaticField"))

/ / static attribute

T.EmitSet ("StaticProperty", "wrong number")

Console.WriteLine (Student.StaticProperty)

Console.WriteLine (t.EmitGet ("StaticProperty"))

ModelOperator.Create (); Student t = new Student (); / / ordinary field t.Name = "Xiaoming"; t.EmitSet ("Name", "the red scarf on Xiaoming's chest is getting brighter!") ; Console.WriteLine (t.Name); Console.WriteLine (t.EmitGet ("Name")); / / General attribute t.EmitSet ("Description", "he loves Xiaogang"); Console.WriteLine (t.Description); Console.WriteLine (t.EmitGet ("Description")); / / static field t.EmitSet ("StaticFiled", "he is next to Xiaogang"); Console.WriteLine (Student.StaticField); Console.WriteLine (t.EmitGet ("StaticField")) / / static attribute t.EmitSet ("StaticProperty", "wrong number"); Console.WriteLine (Student.StaticProperty); Console.WriteLine (t.EmitGet ("StaticProperty")); result:

Case 2:

Support for Column tags

Public class Student: INMSReflector

{

Public string Name

[Column ("Note")]

Public string Description {get; set;}

Public static string StaticField

Public static string StaticProperty {get; set;}

}

Public class Student: INMSReflector {public string Name; [Column ("Note")] public string Description {get; set;} public static string StaticField; public static string StaticProperty {get; set;} Note:

The label here is from System.ComponentModel.DataAnnotations.Schema.

That's why we need using System.ComponentModel.DataAnnotations.Schema.

Usage:

Whether you pass the name of the tag setting or the attribute name, you can assign or get a value.

ModelOperator.Create ()

Student t = new Student ()

T.EmitSet ("Note", "set label")

Console.WriteLine (t.Description)

Console.WriteLine (t.EmitGet ("Note"))

Other:

The ModelOperator class provides more operation functions.

Unlike object's extension method, the first parameter needs to be passed in the instance

/ / get the value of a field and attribute of instance t

Object Get (T t, string propertyName)

/ / set the value of a field and property of instance t

Void Set (T t, string propertyName, object value)

/ / get the type of a field and attribute of type T

Type GetType (string propertyName)

/ / get the setting method cache of type T

Dictionary GetSetCache ()

/ / get the cache of the acquisition method of type T

Dictionary GetGetCache ()

/ / get the property field type cache of type T

Dictionary GetTypeCache ()

/ / get the label and attribute field cache of type T

Dictionary GetMapCache ()

Performance testing:

This is the answer to the question about how to understand the simple reflection library NMSReflector. I hope the above content can be of some help to you. If you still have a lot of doubts to be solved, you can follow the industry information channel for more related knowledge.

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