C\#linq 조회 동적 OrderBy

groupeList 는 원본 데이터 집합 입 니 다.List
sortOrder 는 정렬 형식,desc 또는 asc 입 니 다.
sortName 은 정렬 속성 이름 입 니 다.
1.반사 사용.

private static object GetPropertyValue(object obj, string property)
{
      System.Reflection.PropertyInfo propertyInfo = obj.GetType().GetProperty(property);
      return propertyInfo.GetValue(obj, null);
} 

var resultList = sortOrder == "desc" ? groupList.OrderByDescending(p => GetPropertyValue(p, sortName)) : groupList.OrderBy(p => GetPropertyValue(p, sortName));

//linq  ：
//
var resultList1 = from p in groupList orderby GetPropertyValue(p, m.SortName) select p;

if (sortOrder == "desc")
    resultList1 = from p in groupList orderby GetPropertyValue(p, sortName) descending select p;

2.AsQueryable()호출
범용 System.collections.Generic.IEnumerable를 범용 System.Linq.IQueryable로 변환 합 니 다.

var groupQueryList = groupList.AsQueryable();//here
var tmpList = groupQueryList.OrderBy(sortName, sortOrder);

다음 확장 방법 이 필요 합 니 다:

    public static IOrderedQueryable<T> OrderByDescending<T>(this IQueryable<T> source, string property)
    {
        return ApplyOrder<T>(source, property, "OrderByDescending");
    }
    public static IOrderedQueryable<T> ThenBy<T>(this IOrderedQueryable<T> source, string property)
    {
        return ApplyOrder<T>(source, property, "ThenBy");
    }
    public static IOrderedQueryable<T> ThenByDescending<T>(this IOrderedQueryable<T> source, string property)
    {
        return ApplyOrder<T>(source, property, "ThenByDescending");
    }
    static IOrderedQueryable<T> ApplyOrder<T>(IQueryable<T> source, string property, string methodName) {
        string[] props = property.Split('.');
        Type type = typeof(T);
        ParameterExpression arg = Expression.Parameter(type, "x");
        Expression expr = arg;
        foreach(string prop in props) {
            // use reflection (not ComponentModel) to mirror LINQ
            PropertyInfo pi = type.GetProperty(prop);
            expr = Expression.Property(expr, pi);
            type = pi.PropertyType;
        }
        Type delegateType = typeof(Func<,>).MakeGenericType(typeof(T), type);
        LambdaExpression lambda = Expression.Lambda(delegateType, expr, arg);

        object result = typeof(Queryable).GetMethods().Single(
                method => method.Name == methodName
                        && method.IsGenericMethodDefinition
                        && method.GetGenericArguments().Length == 2
                        && method.GetParameters().Length == 2)
                .MakeGenericMethod(typeof(T), type)
                .Invoke(null, new object[] {source, lambda});
        return (IOrderedQueryable<T>)result;
   }

참고:http://stackoverflow.com/questions/41244/dynamic-linq-orderby-on-ienumerablet#41262

C\#linq 조회 동적 OrderBy

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