Re: Input format was not in correct format for int? Followed by "Invalid expression term try" - C# Discussion Boards

Reflection for non public type in Unit Testing

Member 91405151-Mar-16 18:23

1-Mar-16 18:23

Hi All,

I am new to Unit Testing. Need your help in understanding how to use reflection in unit test case.i am using N-Unit Framework for writing unit test.

How to write unit test case for function "GetStudentinfo" in which private field "Studentresult" is updating. How to check this list value in unit test in order to compare expected and actual value using Assertions.

class Updatestdinfo
{
        private enum Result
        {
            Firstclass,
            secondclass
        }
        private List<int, Result > Studentresult = new List<int, Result >();

    public void GetStudentinfo()
    {
      Studentresult[0] = Result.secondclass; 
    }
}

I tried to use reflection [gettype, getmethod] inorder to get the ENum type so that i can define list to initialize the expected value which can be used in Assert method. But its not returning the type of object. How can i resolve this?

modified 2-Mar-16 0:31am.

Re: Reflection for non public type in Unit Testing

Bernhard Hiller1-Mar-16 21:26

Bernhard Hiller

1-Mar-16 21:26

In the .Net world, a test class can inherit from the class under test.

[TestFixture]
public class UpdatestdinfoTests : Updatestdinfo

Change the access modifiers from private to protected, and voila, it works. No reflection required.

Re: Reflection for non public type in Unit Testing

Member 91405152-Mar-16 19:18

Member 9140515

2-Mar-16 19:18

Thanks for your fast reply.
You are suggesting me to change the access modifier from private to protected.But i don't want to change the design of code for unit testing purpose.So how can i proceed?

Regards,
Mala

modified 3-Mar-16 1:33am.

Re: Reflection for non public type in Unit Testing

Bernhard Hiller2-Mar-16 20:42

Bernhard Hiller

2-Mar-16 20:42

Take a look at
Michael C. Feathers: Working Effectively with Legacy Code

Re: Reflection for non public type in Unit Testing

BillWoodruff2-Mar-16 2:53

BillWoodruff

2-Mar-16 2:53

May I suggest you read the discussion here: [^], and think about whether unti-testing of the private "details" of your objects is really a requirement.

But, if you have to do it, note that Microsoft's testing facility hands you tools like 'PrivateObject and 'PrivateType.

Without seeing your code where you try and test an 'Enum, I don't think much can be said except that, yes, it can be done.

«In art as in science there is no delight without the detail ... Let me repeat that unless these are thoroughly understood and remembered, all “general ideas” (so easily acquired, so profitably resold) must necessarily remain but worn passports allowing their bearers short cuts from one area of ignorance to another.» Vladimir Nabokov, commentary on translation of “Eugene Onegin.”

Re: Reflection for non public type in Unit Testing

Member 91405152-Mar-16 19:37

Member 9140515

2-Mar-16 19:37

Thanks for the info.

Yes i wanted to check the private variable in unit testing as the method is having void as return type. So decided to check the variable values in order to do assertions.

I am able to get the private primitive data type [int, string] variables. but facing issue in accessing private custom data type i.e., user defined data types.

So please help me out.

Input format was not in correct format for int? Followed by "Invalid expression term try"

Sam 91001-Mar-16 8:26

Sam 9100

1-Mar-16 8:26

/*I retrieve key value pairs for each of the conditions. The error is in the bolded. First condition returns longitude & latitude pairs. The third condition returns "State" and "WY" or "County"and "Buffalo", so that works fine. If it contains an "ID", it errors when the kvp consist of "value" = LocationID (corresponds to column name) that has empty string in uppercase "Value", because some are empty in the database */

/// <summary>
/// Parse a set of values into an instance of tbl_Mine_MineGroup using Reflection
/// </summary>
        public static tbl_Location ParseLocation(IOrderedDictionary values)
        {
            tbl_Location locFromValues = new tbl_Location();
            
            // use reflection to update properties, because I'm lazy
            foreach (DictionaryEntry value in values)
            {
                if (value.Key.Equals("Latitude") || 
value.Key.Equals("Longitude"))
                {
                    double? valueAsNumber = null;
                    try { valueAsNumber = double.Parse(value.Value.ToString()); }
                    catch { }

                    locFromValues.GetType().GetProperty(value.Key.ToString()).SetValue(locFromValues, valueAsNumber);
                }
                else if (value.Key.ToString().Contains("ID"))
                {
                    int? valueAsNumber = null;
                    try { valueAsNumber = int.Parse(value.Value.ToString()); }
                    catch { }

                    locFromValues.GetType().GetProperty(value.Key.ToString()).SetValue(locFromValues, valueAsNumber);
                }
                else
                {
                    locFromValues.GetType().GetProperty(value.Key.ToString()).SetValue(locFromValues, value.Value);
                }
            }

            return locFromValues;<pre lang="c#">

//I tried several ways for nullable int to take empty strings but it doesn't work, without adding another return in the catch. I have a return at the end of code block. Thank you.

Re: Input format was not in correct format for int? Followed by "Invalid expression term try"

Eddy Vluggen1-Mar-16 9:07

Eddy Vluggen

1-Mar-16 9:07

Sam 9100 wrote:
try { valueAsNumber = int.Parse(value.Value.ToString()); }
catch { }

That's a cardinal sin; an empty catch-block hides any error and acts as if nothing happened.

There's Int32.TryParse[^], which you might want to try;

if (!Int32.TryParse(Convert.ToString(value.Value), out valueAsNumber)
  valueAsNumber = 0;

You could explicitly check for DBNull.Value and assign a value for empty-fields only, but the above would assume that everything that can't be converted to a number is equal to zero.

Do take into consideration that the example is non-localized and simplified; you might need to specify which culture you are expecting to validate the string correctly as a number.

Bastard Programmer from Hell Suspicious | :suss:

If you can't read my code, try converting it here[^]

Re: Input format was not in correct format for int? Followed by "Invalid expression term try"

Sam 91001-Mar-16 12:08

Sam 9100

1-Mar-16 12:08

Thank you for the reply Eddie. That code did not work either. I wish I could post screen shot for you. I inherited this project so here is more info to help.

This BLL code loops thru COLs and values with same values in the db. This particular field is datatype int that allows null. Due to key value pairs, the .Contains("ID") will show key=StatusID value=2004 (which works fine), or key=PostID value="". If empty strings, it shows null for int? Hence the "input string incorrect format" error.

int? valueAsNumber = null; shows null

During debug, the begin code and next step after this section wants it as an int. Here due to the key pair values, it does not like empty strings. But it allows null in db? It also says "to ignore exceptions to retain NULL when parsing" only in this section are the Catch blocks empty.
This is MVC, Entity Framework 6.1, C#, asp.net 4.5

I also tried if the value contains("ID") or Contains("") or == null, it didnt like it. The textbox expects an int returned

Re: Input format was not in correct format for int? Followed by "Invalid expression term try"

Matt T Heffron1-Mar-16 13:35

Matt T Heffron

1-Mar-16 13:35

Eddie's right about the code smell of the try with an empty catch. Use int.TryParse to determine if there's a parsing error.
If value.Value is an empty string then the parsing will fail.
(Since you aren't getting a NullReferenceException on the .ToString() it means that value.Value isn't null.)
So what you should do first is to check value.Value for being empty.

/// <summary>
/// Parse a set of values into an instance of tbl_Mine_MineGroup using Reflection
/// </summary>
public static tbl_Location ParseLocation(IOrderedDictionary values)
{
  tbl_Location locFromValues = new tbl_Location();
  Type locType = typeof(tbl_Location);    // we KNOW this
            
  // use reflection to update properties, because I'm lazy
  foreach (DictionaryEntry value in values)
  {
    string key = value.Key as string;
    if (key == null)
      throw new InvalidOperationException(string.Format("Key is not a string: {0}", value.Key);
    string val = value.Value as string;
    bool emptyValue = string.IsNullOrEmpty(val);
    object storableValue = null;

    if (key.Equals("Latitude") || key.Equals("Longitude"))
    {
      double parsed;
      // if the parse fails treat it the same as empty and leave storableValue null
      if (!emptyValue && double.TryParse(val, out parsed))
        storableValue = parsed; 
    }
    else if (key.Contains("ID"))
    {
      int parsed;
      // if the parse fails treat it the same as empty and leave storableValue null
      if (!emptyValue && int.TryParse(val, out parsed))
        storableValue = parsed; 
    }
    else
    {
      storableValue = val;
    }
    // storableValue has null or the "boxed" values of the parsed numeric values or the string
    // this is equivalent to using double? and int? above
    locType.GetProperty(key).SetValue(locFromValues, storableValue);
  }
 
  return locFromValues;
}

All of a sudden you mention TextBox.
The TextBox's .Text property expects a string value.
So where is the value from the PostID property of the tbl_Location get put into this TextBox's .Text property you mention?
That is probably where the "null" from "parsing" the empty string gets displayed.

"Fairy tales do not tell children the dragons exist. Children already know that dragons exist. Fairy tales tell children the dragons can be killed."
- G.K. Chesterton

Re: Input format was not in correct format for int? Followed by "Invalid expression term try"

Sam 91003-Mar-16 4:28

Sam 9100

3-Mar-16 4:28

Sorry for the late reply, but thank you both for your help. There is more to it than this from what I investigate. However, I have replaced the empty catch block with the if else TryParse. It is cleaner and better. What this is supposed to do is retrieve matching data from gridviewOne and gridviewTwo, and displaying results in gridviewResults with a new ID. The db is returning the ID to the BLL class (above), but it does not return all the way to the view forms. So the actual error has been resolved, but a prior change (undocumented) occurred where an ID was overridden so the next error I generate is object null reference error. My CO brought me in to fix the bug because no one knows what happened. But I appreciate your assistance and I will gladly post for more help as you guys are the best! Keep up the good work!

Why getting Error :Column name doesn't belong to table

Veena Hosur29-Feb-16 23:32

Veena Hosur

29-Feb-16 23:32

I am getting error in the bold line. i have column name as paword but its showing column name doesnt belong to the table

public Userdetails GetUserDetailsByEmailID(String EmailID)
       {
           Userdetails userInfobyEmailID = null;

           NpgsqlParameter[] parameters = new NpgsqlParameter[]    {
               new NpgsqlParameter("@email", EmailID)
           };

           using (DataTable table = Helper.ExecuteParamerizedSelectCommand("forgetpassword", CommandType.StoredProcedure, parameters))
           {
               //check if any record exist or not
               if (table.Rows.Count > 0)
               {
                   userInfobyEmailID = new Userdetails();

                   foreach (DataRow row in table.Rows)
                   {

                       userInfobyEmailID.paword = Utilities.Decrypt(row["paword"].ToString());
                   }

               }

               return userInfobyEmailID;
           }

       }

Re: Why getting Error :Column name doesn't belong to table

Richard MacCutchan1-Mar-16 0:00

Richard MacCutchan

1-Mar-16 0:00

Are you certain that is the correct spelling of the column name?

Re: Why getting Error :Column name doesn't belong to table

Veena Hosur1-Mar-16 0:08

Veena Hosur

1-Mar-16 0:08

no in table also name is same

Re: Why getting Error :Column name doesn't belong to table

Richard MacCutchan1-Mar-16 0:25

Richard MacCutchan

1-Mar-16 0:25

I find that hard to believe. Show the exact details of what gets posted into your DataTable from the stored procedure.

Re: Why getting Error :Column name doesn't belong to table

Richard MacCutchan1-Mar-16 0:06

Richard MacCutchan

1-Mar-16 0:06

Also, please do not post the same question in a forum and QA.

Re: Why getting Error :Column name doesn't belong to table

Sascha Lefèvre1-Mar-16 0:13

Sascha Lefèvre

1-Mar-16 0:13

Did you miss all those replies to your last question where we suggested you read up on how to securely handle passwords in your application? Or did you just choose to ignore them?

If the brain were so simple we could understand it, we would be so simple we couldn't. — Lyall Watson

Re: Why getting Error :Column name doesn't belong to table

Luc Pattyn1-Mar-16 2:35