我有一个名为filterTarget嵌套列表。
有关内容例如:
filterTarget = { Id: 1
InventoryDescription: {Type: "Machine", Code: "1/1", Description: "1", Category: "1", StockCode: "1", …}
InventoryRecordDetails: []
Length: "1"
Life: "04.02.2019"
Location: null
Model: "1" }
这个例子我想InventoryDescription准则的价值。
我写此代码为两层,但它看起来脏和不足。和它的不一般。
filterTarget = filterTarget
.Where(x => x.GetType()
.GetProperty(fieldval1)
.PropertyType
.GetProperty(fieldval2)
.GetValue(x.GetType()
.GetProperty(fieldval1)
.GetValue(x))
.ToString()?
.ToLower() == deger)
.ToList();
如何从与反思和LINQ嵌套列表值?
如果你正在寻找一个LINQ的解决方案,然后let
会是您的朋友:
filterTarget = (from f in filterTarget
let temp = f.GetType().GetProperty(fieldval1).GetValue(f)
let temp2 = temp.GetType().GetProperty(fieldval2).GetValue(temp)
where temp2.ToString().ToLower() == deger
select f).ToList();
但我个人觉得这相当不可读。用适当的,如果条件一个正常的循环会更容易维护:
public IEnumerable<T> FilterMyList<T>(IEnumerable<T> list, string fieldval1, string fieldval2, string deger)
{
foreach (var element in list)
{
var nesteValue1 = element.GetType().GetProperty(fieldval1).GetValue(element);
var nestedValue2 = nesteValue1.GetType().GetProperty(fieldval2).GetValue(nesteValue1);
if (nestedValue2.ToString().ToLower() == deger)
{
yield return element;
}
}
}
下面是一个使用递归潜入你的嵌套的对象更广泛的方式。您需要提供propertynames的确切金额,它必须匹配嵌套结构的水平:
public IEnumerable<T> FilterMyListRecursive<T>(IEnumerable<T> list, string searchpattern, params string [] propertynames) where T: class
{
foreach (var element in list)
{
if (TryNestedRecursiveDescend(element, searchpattern, propertynames))
{
yield return element;
}
}
}
private bool TryNestedRecursiveDescend<T>(T obj, string searchpattern, params string [] propertynames) where T: class
{
var nestedValue = obj.GetType().GetProperty(propertynames.First()).GetValue(obj);
// if you are at the lowest level that you can check
if (fieldvalues.Length == 1)
{
return nestedValue.ToString().ToLower() == searchpattern;
}
else
{
// recursive call with the remaining propertynames
return TryNestedDescend(nestedValue, searchpattern, propertynames.Skip(1).ToArray());
}
}
filterTarget是我的嵌套列表。
现场订购属性字符串。
filterTarget = (from f in filterTarget
let temp = GetPropertyValue(f, Field)
where temp?.ToString().ToLower() == "deger"
select f).ToList();
private static object GetPropertyValue<T>(T filterTarget, string field)
{
string[] fields = field.Split('.');
object value = filterTarget;
fields?.ToList().ForEach(p =>
{
value = value.GetType().GetProperty(p).GetValue(value);
});
return value;
}