Unable to produce a chart using linq in csharp

I am coding in Microsoft Visual Studio 12 in ASP.net using c# and a noob at it.

This is what csv file looks like

ID, Engine Type, Car
111,vtec, 1
131,vtec, 1
157,boxer,1
148,boxer,1
167,vtec,1
158,,0
107,,0

ID should be a generic autonumber, Engine Type should be a type string and I don’t know what Car should because it consists off 1’s and 0’s representing Boolean. This means that 1-customer has a car and 0 means that customer doesn’t have a car.

This is how i create a list out of it.

var testingobject = (
    from line in File.ReadAllLines("testing.csv").Skip(0)
    let parts = line.Split(',')
    select new
    {
        ID = parts[0],
        Engine_Type = parts[1],
        Car = parts[2] //should i put int32.parse(parts[2]) here
    ).ToList();

I create a simple array which consists of ID,Engine Type,Car convert it to a list using ToList() and then bind it to a dropdownlist, using this code:

string[] testingddl = new string[] { "ID", "Engine Type", "Car" };
List<String> mytestinglist = testingddl.ToList();
var mytestin = from m in mytestinglist
select m;
DropDownList1.DataSource = mytestin.AsEnumerable();
DropDownList1.DataTextField = "";
DropDownList1.DataValueField = "";
DropDownList1.DataBind();

User selects Car and should give me the a chart that has engine type in x-axis and total on y-axis.

The Problem: The column consists of 1’s and 0’s meaning whether the customer has a car (1) or doesnt (0).
I would like to view how many users have different types of engines types and bind it to a, say a column chart. So the data should display on the x-axis, engine type and y-axis should have the total. according to the data, there are 3 vtecs and 2 boxers. So vtecs represent a column with 3 total and boxers with 2.

I use this linq query and the following chart binding code.

if (tempval == "Car")// this is the current selected dropdown list value
{
    var myfavitems = testingobject.Where(a => a.Car == "1").ToList();
    foreach (var t in myfavitems.GroupBy(a => a.Engine_Type))
    {
        Series Series1 = new Series();
        Chart1.Series.Add(Series1);
        Chart1.Series[1].Points.AddXY(t.Key.ToString(), t.Count().ToString()).ToString();
        Chart1.DataSource = myfavitems.AsEnumerable();
        Chart1.Series[1].XValueMember = "Group Equipment Type";
        Chart1.Series[1].YValueMembers = "Software";
        Chart1.DataBind();
    // ...??

The error comes at the point where I am reading my columns from the csv files. The error says Format exception was unhandled by user code: Input string was not in a correct format

select new  
{
    ID = parts[0],
    Engine_Type = parts[1],
    Car = Int32.Parse(parts[2])
}

I dont know what is wrong with that statement. Could someone please help me out.

Answers:

Thank you for visiting the Q&A section on Magenaut. Please note that all the answers may not help you solve the issue immediately. So please treat them as advisements. If you found the post helpful (or not), leave a comment & I’ll get back to you as soon as possible.

Method 1

You will want to have a class like this:

public class CarClass {
    public int Id { get; set; }
    public string Engine { get; set; }
    public int Car { get; set; }
}

And then do something like:

var car_collection =
    from line in File.ReadAllLines("your_csv_name.csv").Skip(1)
    let parts = line.Split(',')
    select new CarClass()
    {
        Id = Int32.Parse(parts[0]),
        Engine = parts[1],
        Car = Int32.Parse(parts[2])
    };

var listy = car_collection.ToList();

Otherwise, notice the ‘{ }’ and the ‘( )’ , because yours don’t match:

var car_collection =
    (from line in File.ReadAllLines("your_csv_name.csv").Skip(1)
    let parts = line.Split(',')
    select new CarClass()
    {
        Id = Int32.Parse(parts[0]),
        Engine = parts[1],
        Car = Int32.Parse(parts[2])
    }).ToList();

That should solve your problem with the error

Method 2

If your header row is in CSV file then

Car = Int32.Parse(parts[2])

is trying to parse "Car" to Int32.

Try reading file with:

File.ReadAllLines("testing.csv").Skip(1)

to skip header row.

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0