Reflection does not respect @ symbol with reserved keyword classes

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• C# - Adding condition to func results in stack overflow exception

  I have a func as part of specification class which sorts the given iqueryable

  Func<IQueryable<T>, IOrderedQueryable<T>>? Sort { get; set; }
  

  When i add more than one condition to the func like below , it results in stack overflow exception.

  spec.OrderBy(sc => sc.Case.EndTime).OrderBy(sc => sc.Case.StartTime);
  

  The OrderBy method is implemented like this

  public ISpecification<T> OrderBy<TProperty>(Expression<Func<T, TProperty>> property)
      {
          _ = Sort == null ? Sort = items => items.OrderBy(property) : Sort = items => Sort(items).ThenBy(property);
          return this;
      }
  

  Chaining or using separate lines doesn't make a difference.

  This problem gets resolved if I assign a new instance of the specification and set it's func, but i don't want to be assigning to a new instance everytime. Please suggest what am i missing here and how to reuse the same instance (if possible).
• How to projection fields for a dictionary (C#, MongdoDB)

  I am trying my luck here, I have a model which is like the following

  public class RowData : BaseBsonDefinition
  {
  .
    [BsonExtraElements]
    [BsonDictionaryOptions(DictionaryRepresentation.ArrayOfDocuments)]
    public Dictionary<string, object> Rows { get; set; } = new(StringComparer.OrdinalIgnoreCase);
  .
  }
  
  

  In result, the schema in the MongoDB looks like

  {
  "_id": {
      "$binary": {
        "base64": "HiuI1sgyT0OZmcgGUit2dw==",
        "subType": "03"
      }
    },
    "c1": "AAA",
    "c8": "Fully Vac",
    "c10": "",
  }
  

  Those c1, c8 and c10 fields are keys from the dictionary, my question is how to dynamic project those fields?

  I tried

  Builders<RowData>.Projection.Exclude(p => "c1")
  

  It seems the MongoDB driver can not handle a value directly.

  Anyone could point me in the correct direction?

  Thanks,
• How do I add new DataSource to an already Databinded CheckBoxList

  i'm building a web form that show Database's item(Tables, Rows, FK,...)

  I have a CheckBoxList of Tables (chkListTable) which will show a new CheckBoxList of Rows (chkListRow) everytime I SelectedIndexChanged from chkListTable. The problem is i can show the items from chkListTable with 1 selected item. But i don't know how to show chkListRow if multiple item from chkListTable are selected.

  Here are my codes:

  aspx:

  <div>
               <asp:Label ID="Label2" runat="server" Text="Table: "></asp:Label>
               <asp:CheckBoxList ID="chkListTable" runat="server"
                   DataTextField="name"
                   DataValueFeild="name"
                   AutoPostBack="true"
                   OnSelectedIndexChanged="chkListTable_SelectedIndexChanged">
               </asp:CheckBoxList>
          </div>
          <div>
               <asp:CheckBoxList ID="chkListRow" runat="server"
               DataTextField="COLUMN_NAME"
               DataValueField="COLUMN_NAME"
               RepeatDirection="Horizontal">
               </asp:CheckBoxList>
          </div>
  

  aspx.cs:

  protected void chkListTable_SelectedIndexChanged(object sender, EventArgs e)
      {
          tableName.Clear();
          
          foreach (ListItem item in chkListTable.Items)
          {
              if(item.Selected)
              {
                  tableName.Add(item.Text.Trim());
              }    
          }
  
          for(int i = 0; i < tableName.Count; i++)
          {
              String query = "USE " + dbname +
                  " SELECT * FROM information_schema.columns" +
                  " WHERE table_name = '" + tableName[i] + "'" +
                  " AND COLUMN_NAME != 'rowguid'";
              chkListRow.DataSource = Program.ExecSqlDataReader(query);
              chkListRow.DataBind(); 
              Program.conn.Close();
          }
      }
  

  Program.cs:

  public static bool Connect()
      {
          if (Program.conn != null && Program.conn.State == ConnectionState.Open)
              Program.conn.Close();
          try
          {
              Program.conn.ConnectionString = Program.constr;
  
              Program.conn.Open();
  
              return true;
          }
  
          catch (Exception e)
          {
              return false;
          }
      }
  
      public static SqlDataReader ExecSqlDataReader(String query)
      {
          SqlDataReader myreader;
          SqlCommand sqlcmd = new SqlCommand(query, Program.conn);
          sqlcmd.CommandType = CommandType.Text;
          if (Program.conn.State == ConnectionState.Closed) Program.conn.Open();
          try
          {
              myreader = sqlcmd.ExecuteReader();
              return myreader;
              myreader.Close();
          }
          catch (SqlException ex)
          {
              Program.conn.Close();
              return null;
          }
      }
  

  I want my display to be like this:

  [x]Table1 [x]Table2 [ ]Table3
  [ ]Row1(Table1) [ ]Row2(Table1) [ ]Row3(Table1)
  [ ]Row1(Table2) [ ]Row2(Table2)
  
• C# Reflection GetValue is Replacing certain characters with?

  Using .NET 5, I have two Lists of the same class List. One was generated from Entity Framework from a SQL database and the other using Oracles DataManagedAccess library (if it matters) from a Oracle database. At this point, per what VS debugger shows, the strings in question are correct.

              foreach (var PairedCustomer in PairedCustomers)
              {
                  bool MakeProp = false;
                  //compare properties we care about (defined in mapping)
                  foreach (string prop in PropertiesWeCareAbout)
                  {
                      string tProp = PairedCustomer.TargetCustomer.GetType().GetProperty(prop).GetValue(PairedCustomer.TargetCustomer, null).ToString(); 
                      string dProp = PairedCustomer.DCustomer.GetType().GetProperty(prop).GetValue(PairedCustomer.DCustomer, null).ToString();
  

  What the issue is, in the above code "PairedCustomer.TargetCustomer" has a string value in the object as "für Fischerei" however, the tProp value is showing up as: "f?r Fischerei". It does this with all umlaut and similar characters but only for the List that came from Oracle. Why does it appear correct in the List (via VS debugger), but is replaced with ? when using reflection (Yes... I hate using reflection, but I don't have a better way at the moment).

  
• C# Reflection get the instance behind FieldInfo

  I am having an issue with Reflection, which I can't seem to find a solution for.

  I have the following simple interface :

      public interface IDataProperty<T> 
  {
     public T Value { get; set; } 
     public int BytesCount();
     public byte[] Serialize();
  }
  

  the struct which implements the interface above :

      public struct IntProperty : IDataPropery<int> 
  {
      private int _value; 
      public int Value { get => _value; set => _value = value; }
  
      public int BytesCount()
      {
          return 4;
      }
  
      public byte[] Serialize()
      {
          return BitConverter.GetBytes(_value);
      }
      public IntDataProperty(int value) { _value = value; }
  }
  

  and a simple class to hold the values :

  public class ValuesContainer  
  {
     public IntProperty prop1;
     public IntProperty prop2;
  }
  

  I am trying to call the Serialize() method on both prop1 and prop2 in my Processor class, with no luck so far... :

  public class Processor  
  {
     public void ProccesData<T>(out T result) where T : ValuesContainer, new() 
      {
        result = new T();
          List<FieldInfo> dataFields = new List<FieldInfo>();
          result.GetType().GetFields().ToList().ForEach(field => { 
          if(field.FieldType.GetInterfaces().Any(i => i.IsGenericType && i.GetGenericTypeDefinition() == typeof(IDataProperty<>)))
              {
                  dataFields.Add(field);
              }
                });
           MethodInfo serializeMI = typeof(IDataProperty<>).GetMethod("Serialize");
           foreach(FieldInfo field in dataFields)
          {
              Console.WriteLine(field.Name);
              serializeMI.Invoke(field,null);
          }
  
      }
  }
  

  Running the code at this point gives me the following error :

  'Late bound operations cannot be performed on types or methods for which ContainsGenericParameters is true.'
  

  I am aware that I need to get somehow to the instance behind the field variable, but have no idea how to do it. Does anyone know a good way of doing what i am trying to achieve using other methods, or only Reflection is the way to go, and if the latter - what solutions do I have ?

  Thanks in advance to all of you.
• Pass a method to another method as parameter using expression tree in c#

  I have a class like:

  class First {
      public void Handler(User user) {
          ...
      }
  }
  

  and i have a function that is generated in runtime using expression trees.

  Func<Action<object>> cb = () => {
      var src = new Src<User>();
  
      return hander_func => src.Callback((Action<User>)hander_func);
  }
  

  I need to call returned function with expression trees. Like:

  cb(First.Handler)
  

  But i can't find a way to get function pointer in expression trees.