How to Implement Dynamic LINQ OrderBy on `IQueryable` and `IEnumerable`?

Use dynamic linq orderby

on and IQueryable<T> IEnumerable<T> When using linq, you often sort the results set. Linq provides and

methods to achieve this. However, these methods are designed to operate

data sources, not OrderBy data sources. OrderByDescending IQueryable<T> To sort the data source, you need to use the IEnumerable<T> method to convert it to

before you can apply the

or IEnumerable<T> method. However, converting to is not always feasible or efficient. AsQueryable IQueryable<T> Implement Orderby OrderBy OrderByDescending The following code fragment provides the implementation of the IQueryable<T> data source

and

methods: IEnumerable<T>

This implementation is divided into the specified attribute path into a single attribute name, and a reflection is used to generate an expression tree. This expression tree can be used to dynamically create IEnumerable<T> or OrderBy expressions. OrderByDescending

Integrated dynamic linq

public static IOrderedEnumerable<T> OrderBy<T>(
    this IEnumerable<T> source,
    string property)
{
    return ApplyOrder<T>(source, property, "OrderBy");
}

public static IOrderedEnumerable<T> OrderByDescending<T>(
    this IEnumerable<T> source,
    string property)
{
    return ApplyOrder<T>(source, property, "OrderByDescending");
}

static IOrderedEnumerable<T> ApplyOrder<T>(
    IEnumerable<T> source,
    string property,
    string methodName)
{
    //  此处省略部分代码，因为原代码不完整且存在错误，无法直接运行。需要补充完整的代码逻辑才能实现动态排序。
}

In order to further enhance the function, you can integrate this with dynamic Linq, which allows you to specify the sorting expression as a string similar to SQL. This is an example: <> OrderBy OrderByDescending In this example,

and

methods use dynamic data sources and attribute paths as input, and use the

class as a specified attribute path to dynamically generate attribute accessors.

Class provides an efficient cache and lock mechanism to ensure that the attribute accessor is created only once.

public static IOrderedEnumerable<dynamic> OrderBy(
    this IEnumerable<dynamic> source,
    string property)
{
    return Enumerable.OrderBy<dynamic>(
        source,
        AccessorCache.GetAccessor(property),
        Comparer<object>.Default);
}

public static IOrderedEnumerable<dynamic> OrderByDescending(
    this IEnumerable<dynamic> source,
    string property)
{
    return Enumerable.OrderByDescending<dynamic>(
        source,
        AccessorCache.GetAccessor(property),
        Comparer<object>.Default);
}

This integration allows you to use more expressive grammar when sorting dynamic data sources, so as to more easily write query involving complex margins. It should be noted that the implementation details of the class are not provided in the original text, and the appropriate third -party library needs to be implemented or using it. In addition, the method in the original code is incomplete, and the complete code logic needs to be supplemented to achieve dynamic sorting function.

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