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C# Generic search in object recursively [duplicate]

This question already has answers here:
Recursively Get Properties & Child Properties Of A Class
(5 answers)
Closed 2 years ago.
I am trying to write an universal search to use for all objects.
I have this code, which is working fine to search in just one object's properties, but I would also like to search also in properties in related objects.
Eg. I have these Models/Objects
public class Customer
{
public int Id { get; set; }
public string Name { get; set; }
public int Age { get; set; }
public string Address{ get; set; }
public ICollection<Contract> Contracts { get; set; }
}
public class Contract
{
public int Id { get; set; }
public DateTime From{ get; set; }
public DateTime To{ get; set; }
public string Comment{ get; set; }
public int CustomerId { get; set; }
[ForeignKey("CustomerId")]
public Customer Customer { get; set; }
}
and I want to search if any of properties contains some a string eg. "Peter", I will call it this way:
string searchString = "Peter";
var customers = db.Customers
.Include(x => x.Contracts)
.WhereAnyPropertiesOfSimilarTypeContains(searchString);
this code will check if any properties of 'Customer' contains string "Peter".
But I would also need to check if the related model 'Contract' contains "Peter.
public static class EntityHelper
{
public static IQueryable<TEntity> WhereAnyPropertiesOfSimilarTypeContains<TEntity, TProperty>(this IQueryable<TEntity> query, TProperty value)
{
var param = Expression.Parameter(typeof(TEntity));
var predicate = PredicateBuilder.False<TEntity>(); //--- True to equal
var entityFields = GetEntityFieldsToCompareTo<TEntity, TProperty>();
foreach (var fieldName in entityFields)
{
MethodInfo method = typeof(string).GetMethod("Contains", new[] { typeof(string) });
var predicateToAdd = Expression.Lambda<Func<TEntity, bool>>(
Expression.Call(
Expression.PropertyOrField(param, fieldName), method,
Expression.Constant(value)), param);
predicate = predicate.Or(predicateToAdd); //--- And to equal
}
return query.Where(predicate);
}
// TODO: You'll need to find out what fields are actually ones you would want to compare on.
// This might involve stripping out properties marked with [NotMapped] attributes, for
// for example.
public static IEnumerable<string> GetEntityFieldsToCompareTo<TEntity, TProperty>()
{
Type entityType = typeof(TEntity);
Type propertyType = typeof(TProperty);
var fields = entityType.GetFields()
.Where(f => f.FieldType == propertyType)
.Select(f => f.Name);
var properties = entityType.GetProperties()
.Where(p => p.PropertyType == propertyType)
.Select(p => p.Name);
return fields.Concat(properties);
}
}
Thanks.

After reread the question. I don't know what are you trying, but here I put the idea I have what are you looking for.
public class Customer : AbstractEntity
{
public int Id { get; set; }
public string Name { get; set; }
public int Age { get; set; }
public string Address { get; set; }
public ICollection<Contract> Contracts { get; set; }
}
public class Contract : AbstractEntity
{
//what property here can be string "Peter"? Comments?
//what are you trying?
public int Id { get; set; }
public DateTime From { get; set; }
public DateTime To { get; set; }
public string Comment { get; set; }
public int CustomerId { get; set; }
[ForeignKey("CustomerId")]
public Customer Customer { get; set; }
}
public abstract class AbstractEntity
{
//this method can be used to preselect properties you want
protected virtual Tuple<bool, ICollection<PropertyInfo>> PropertyCollector()
{
return new Tuple<bool, ICollection<PropertyInfo>>(false, null);
}
public IEnumerable<Tuple<Type, object>> GetRowValues()
{
foreach (var prop in GetRows())
{
yield return new Tuple<Type, object>(prop.PropertyType, prop.GetValue(this));
}
}
public ICollection<PropertyInfo> GetRows()
{
var tuple = PropertyCollector();
ISet<PropertyInfo> pInfo;
if (tuple.Item1)
{
pInfo = new HashSet<PropertyInfo>(tuple.Item2);
}
else //search all non virtual, private, protected properties, "following POCO scheme"
{
pInfo = new HashSet<PropertyInfo>();
foreach (var prop in GetType().GetProperties())
{
foreach (var access in prop.GetAccessors())
{
if ((!access.IsVirtual && !access.IsPrivate) && (prop.CanWrite && prop.CanRead))
{
pInfo.Add(prop);
}
}
}
}
return pInfo;
}
}
public static class Searchs
{
public static ICollection<object> ObjectsWithStringFound(ICollection<Customer> customers, string toBeFound)
{
var objs = new List<object>();
foreach (var cust in customers)
{
var strings = cust.GetRowValues().Where(tpl => tpl.Item1 == typeof(string)).Select(tpl => tpl.Item2);
var contracts = cust.GetRowValues().Where(tpl => tpl.Item2 is IEnumerable<Contract>).Select(tpl => tpl.Item2);
if (strings.Any(str => str == toBeFound))
{
objs.Add(cust);
}
else if (contracts.Any(ctr => ((IEnumerable<Contract>)ctr).!!!!!!!!! == toBeFound))
{ //What I suppose I must "match" with "Peter"??!?!
objs.Add(contracts.First(ctr => ((IEnumerable<Contract>)ctr).!!!!!!!!! == toBeFound));
}
}
return objs;
}
}
I think we aren't understanding each other.

Ignore properties of class by comparing with a list in c#

I have a list where TestClass is a class with some predefined properties. So when i get data and bind my list with data i need to ignore some properties of TestClass by comparing it with a list. How can i achieve that?
Below is my code
public class TestClass
{
public int id{get;set;}
public string fname{get;set;}
public string lname{get;set;}
public string job {get;set;}
public string role{get;set;}
public string address{get;set;}
}
List<TestClass> ulist = null;
ulist = ToList<TestClass>(usersdataset.tables[0]); //fill my list with the data code is given below
so after getting the data into the list i need to remove some properties by comparing it with list of properties which should be returned.for example if my filteredlist should only show id,fname,role then i need to remove the extra properties from my ulist. so after the filter ulist should only contain id,fname and role
ToList Method
public static List<T> ToList<T>(DataTable dataTable) where T : new()
{
var dataList = new List<T>();
//Define what attributes to be read from the class
const BindingFlags flags = BindingFlags.Public | BindingFlags.Instance;
//Read Attribute Names and Types
var objFieldNames = typeof(T).GetProperties(flags).Cast<PropertyInfo>().
Select(item => new
{
Name = item.Name,
Type = Nullable.GetUnderlyingType(item.PropertyType) ?? item.PropertyType
}).ToList();
//Read Datatable column names and types
var dtlFieldNames = dataTable.Columns.Cast<DataColumn>().
Select(item => new {
Name = item.ColumnName,
Type = item.DataType
}).ToList();
foreach (DataRow dataRow in dataTable.AsEnumerable().ToList())
{
var classObj = new T();
foreach (var dtField in dtlFieldNames)
{
PropertyInfo propertyInfos = classObj.GetType().GetProperty(dtField.Name);
var field = objFieldNames.Find(x => x.Name == dtField.Name);
//var field = filteredColumns.Find(x => x.PropertyName == dtField.Name);
if (field != null)
{
if (dataRow[dtField.Name] != DBNull.Value)
propertyInfos.SetValue(classObj, dataRow[dtField.Name], null);
}
}
dataList.Add(classObj);
}
return dataList;
}

Use the overvride function Equals:
This sample compare only the id property
public class TestClass
{
public int id { get; set; }
public string fname { get; set; }
public string lname { get; set; }
public string job { get; set; }
public string role { get; set; }
public string address { get; set; }
public override bool Equals(object obj)
{
if (obj.GetType().Name != this.GetType().Name)
{
return false;
}
TestClass testclassObject = (TestClass)obj;
if (testclassObject.id != this.id)
{
return false;
}
return true;
}

Get Property Value of Nested Classes is always null

I have following two classes
public class Family
{
public string ChildName { get; set; }
}
public class Employee
{
public int Id { get; set; }
public string Name { get; set; }
public Family Child { get; set; }
}
I have an instance of Employee class as follows.
Employee employee = new Employee();
employee.Name = "Ram";
employee.Id = 77;
employee.Child = new Family() { ChildName = "Lava" };
I have a method which gets the property value based on the property name as follows:
public static object GetPropertyValue(object src, string propName)
{
string[] nameParts = propName.Split('.');
if (nameParts.Length == 1)
{
return src.GetType().GetRuntimeProperty(propName).GetValue(src, null);
}
foreach (String part in nameParts)
{
if (src == null) { return null; }
Type type = src.GetType();
PropertyInfo info = type.GetRuntimeProperty(part);
if (info == null)
{ return null; }
src = info.GetValue(src, null);
}
return src;
}
In the above method,when I try to get property value of nested class like
GetPropertyValue(employee, "employee.Child.ChildName")
or
GetPropertyValue(GetPropertyValue(employee, "Family"), "ChildName"
doesn't return any value because type.GetRuntimeProperty(part) is always null.
Is there any way to fix this problem?

You problem lies in this line:
foreach (String part in nameParts)
Because you are iterating over each part of nameParts, you are also iterating over "employee", which of course is not a valid property.
Try either this:
foreach (String part in nameParts.Skip(1))
Or calling the method like this:
GetPropertyValue(employee, "Child.ChildName")
(Notice no "employee.", because you already pass in an employee)

The problem in this case is that when you split the string employee.Child.ChildName, the "employee" is the first part. However, employee is not a property of the source i.e. Employee Class.
Try this:
public class Program
{
public static void Main()
{
Employee employee = new Employee();
employee.Name = "Ram";
employee.Id = 77;
employee.Child = new Family() { ChildName = "Lava" };
GetPropertyValue(employee, "employee.Child.ChildName");
}
public class Family
{
public string ChildName { get; set; }
}
public class Employee
{
public int Id { get; set; }
public string Name { get; set; }
public Family Child { get; set; }
}
public static object GetPropertyValue(object src, string propName)
{
string[] nameParts = propName.Split('.');
if (nameParts.Length == 1)
{
return src.GetType().GetRuntimeProperty(propName).GetValue(src, null);
}
nameParts = nameParts.Skip(1).ToArray();
foreach (String part in nameParts)
{
if (src == null) { return null; }
Type type = src.GetType();
PropertyInfo info = type.GetRuntimeProperty(part);
if (info == null)
{ return null; }
src = info.GetValue(src, null);
}
return src;
}
Here, i have skipped the first part of the string i.e. "employee". However, you can solve the problem by passing Child.ChildName

This question is around 2 years old, but I found a another working solution for you question, which is easy to understand. If you initialize the object in calling calss constructor you can use dot(.) notation to assign or read property. Example -
public class Family{
public string ChildName { get; set; }
}
public class Employee{
public int Id { get; set; }
public string Name { get; set; }
public Family Child { get; set; }
public Employee(){
Child = new Family();
}
}
Employee emp = new Employee();
emp.Family.ChildName = "Nested calss attribute value";

Copy object properties to another

I am using this method to copy properties of one object to another and its working fine.
But today i found that its not working for arrays of different object.
please help me in this.
public static class CopyClass
{
/// <summary>
/// Copies source object properties to target object properties.
/// </summary>
/// <param name="source">The source.</param>
/// <param name="target">The target.</param>
public static void CopyTo(object source, object target)
{
foreach (PropertyInfo propSource in source.GetType().GetProperties())
{
foreach (PropertyInfo propTarget in target.GetType().GetProperties())
{
if (propTarget.Name != propSource.Name) continue;
(propTarget.GetSetMethod()).Invoke(target,
new object[] { propSource.GetGetMethod().Invoke(source, null) });
}
}
}
}

Can you check with this function? I am not sure if this is working with Arrays but it sure does with plain members.
public static object ObjectCopyProperties(this object sourceObject, object targetObject)
{
if (sourceObject == null || targetObject == null)
return null;
var targetInstance = targetObject;
PropertyInfo newProp;
foreach (PropertyInfo prop in sourceObject.GetType().GetProperties())
{
if (prop.CanRead)
{
newProp = targetInstance.GetType().GetProperty(prop.Name);
if (newProp != null && newProp.CanWrite)
{
newProp.SetValue(targetInstance, prop.GetValue(sourceObject, null), null);
}
}
}
return targetInstance;
}

Given the following 2 classes
public class UserType1
{
public DateTime Created { get; set; }
public string First { get; set; }
public Gender Genter { get; set; }
public int Id { get; set; }
public string Last { get; set; }
public DateTime Updated { get; set; }
public string DontMatchType { get; set; }
public string Unique1 { get; set; }
}
public class UserType2
{
public DateTime Created { get; set; }
public string First { get; set; }
public Gender Genter { get; set; }
public int Id { get; set; }
public string Last { get; set; }
public DateTime Updated { get; set; }
public int DontMatchType { get; set; }
public string Unique2 { get; set; }
}
and the following code
UserType1 user1 = new UserType1
{
Id = 1,
First = "John",
Last = "Doe",
Genter = Gender.Male,
Created = DateTime.Now.AddDays(-1),
Updated = DateTime.Now,
DontMatchType = "won't map",
Unique1 = "foobar"
};
UserType2 user2 = CopyTo<UserType2>(user1);
you can see that this mapping function will only map matching name/types
public static T CopyTo<T>(object source)
where T : new()
{
if (source == null) throw new ArgumentException("surce is null", "source");
T target = new T();
source.GetType()
.GetProperties()
.Join(target.GetType().GetProperties()
, s => s.Name
, t => t.Name
, (s, t) => new
{
source = s,
target = t
})
.AsParallel()
.Where(inCommon => inCommon.source.PropertyType == inCommon.target.PropertyType
&& inCommon.source.CanRead && inCommon.target.CanWrite)
.ForAll(inCommon => inCommon.target.SetValue(target, inCommon.source.GetValue(source, null), null));
return target;
}
and you can use
public static IEnumerable<T> CopyTo<T>(IEnumerable<object> source)
where T : new()
{
return source.AsParallel().Select(CopyTo<T>);
}
to copy a collection like this
UserType1[] users1 = new[]
{
new UserType1
{
...
}
};
UserType2[] users2 = CopyTo<UserType2>(users1).ToArray();
This has the added benefit that it will not needlessly loop all the properties of object B for every property in object A, as its using a join to find the properties in common (by name and type).
Mapping can be tricky. You can get into a lot of situations of name/types and nesting. I would suggest Automapper as jjchiw mentioned.

If your object is serializable you can create an extension method which serialize the source object and deserialize it in return
public static class CloneExtensions
{
public static T Clone<T>(this T source)
{
if (!typeof(T).IsSerializable)
{
throw new ArgumentException("The type must be serializable.", "source");
}
if(source == default(T))
return default(T);
IFormatter formatter = new BinaryFormatter();
Stream stream = new MemoryStream();
using (stream)
{
formatter.Serialize(stream, source);
stream.Seek(0, SeekOrigin.Begin);
return (T)formatter.Deserialize(stream);
}
}
}

Remove the null property from object

,I have one class in which I have three properties now what I want to do, if in the object if any one of null or empty then I want to remove it from the object below is my code.
public class TestClass
{
public string Name { get; set; }
public int ID { get; set; }
public DateTime? DateTime { get; set; }
public string Address { get; set; }
}
TestClass t=new TestClass();
t.Address="address";
t.ID=132;
t.Name=string.Empty;
t.DateTime=null;
Now here I want the object of TestClass but in that Name and DateTime property should not be their in the object,
is it possible?
Please help me

There's no such concept as removing a property from an individual object. The type decided which properties are present - not individual objects.
In particular, it will always be valid to have a method like this:
public void ShowDateTime(TestClass t)
{
Console.WriteLine(t.DateTme);
}
That code has no way of knowing whether you've wanted to "remove" the DateTime property from the object that t refers to. If the value is null, it will just get that value - that's fine. But you can't remove the property itself.
If you're listing the properties of an object somewhere, you should do the filtering there, instead.
EDIT: Okay, no you've given us some context:
ok I am using Schemaless database so null and empty value also store space in database that's the reason
So in the code you're using which populates that database, just don't set any fields which corresponds to properties with a null value. That's purely a database population concern - not a matter for the object itself.
(I'd also argue that you should consider how much space you'll really save by doing this. Do you really care that much?)

I was bored and got this in LINQPad
void Main()
{
TestClass t=new TestClass();
t.Address="address";
t.ID=132;
t.Name=string.Empty;
t.DateTime=null;
t.Dump();
var ret = t.FixMeUp();
((object)ret).Dump();
}
public static class ReClasser
{
public static dynamic FixMeUp<T>(this T fixMe)
{
var t = fixMe.GetType();
var returnClass = new ExpandoObject() as IDictionary<string, object>;
foreach(var pr in t.GetProperties())
{
var val = pr.GetValue(fixMe);
if(val is string && string.IsNullOrWhiteSpace(val.ToString()))
{
}
else if(val == null)
{
}
else
{
returnClass.Add(pr.Name, val);
}
}
return returnClass;
}
}
public class TestClass
{
public string Name { get; set; }
public int ID { get; set; }
public DateTime? DateTime { get; set; }
public string Address { get; set; }
}

Hereby a 'slightly' more clear and shorter version of the accepted answer.
/// <returns>A dynamic object with only the filled properties of an object</returns>
public static object ConvertToObjectWithoutPropertiesWithNullValues<T>(this T objectToTransform)
{
var type = objectToTransform.GetType();
var returnClass = new ExpandoObject() as IDictionary<string, object>;
foreach (var propertyInfo in type.GetProperties())
{
var value = propertyInfo.GetValue(objectToTransform);
var valueIsNotAString = !(value is string && !string.IsNullOrWhiteSpace(value.ToString()));
if (valueIsNotAString && value != null)
{
returnClass.Add(propertyInfo.Name, value);
}
}
return returnClass;
}

You could take advantage of the dynamic type:
class Program
{
static void Main(string[] args)
{
List<dynamic> list = new List<dynamic>();
dynamic
t1 = new ExpandoObject(),
t2 = new ExpandoObject();
t1.Address = "address1";
t1.ID = 132;
t2.Address = "address2";
t2.ID = 133;
t2.Name = "someName";
t2.DateTime = DateTime.Now;
list.AddRange(new[] { t1, t2 });
// later in your code
list.Select((obj, index) =>
new { index, obj }).ToList().ForEach(item =>
{
Console.WriteLine("Object #{0}", item.index);
((IDictionary<string, object>)item.obj).ToList()
.ForEach(i =>
{
Console.WriteLine("Property: {0} Value: {1}",
i.Key, i.Value);
});
Console.WriteLine();
});
// or maybe generate JSON
var s = JsonSerializer.Create();
var sb=new StringBuilder();
var w=new StringWriter(sb);
var items = list.Select(item =>
{
sb.Clear();
s.Serialize(w, item);
return sb.ToString();
});
items.ToList().ForEach(json =>
{
Console.WriteLine(json);
});
}
}

May be interfaces will be handy:
public interface IAdressAndId
{
int ID { get; set; }
string Address { get; set; }
}
public interface INameAndDate
{
string Name { get; set; }
DateTime? DateTime { get; set; }
}
public class TestClass : IAdressAndId, INameAndDate
{
public string Name { get; set; }
public int ID { get; set; }
public DateTime? DateTime { get; set; }
public string Address { get; set; }
}
Creating object:
IAdressAndId t = new TestClass()
{
Address = "address",
ID = 132,
Name = string.Empty,
DateTime = null
};
Also u can put your interfaces in separate namespace and make your class declaration as internal. After that create some public factories which will create the instances of your classes.