[RESOLVED] Reading csv data and storing it to array

HI,

I was able to read the csv data and display the data in the Datagridview but I didn't know how to save those data in array form. My code looks like following:

Code:

---

  Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click


        Try
            OpenFileDialog1.ShowDialog()

            Using MyReader As New Microsoft.VisualBasic.
                            FileIO.TextFieldParser(OpenFileDialog1.FileName)
                MyReader.TextFieldType = FileIO.FieldType.Delimited
                MyReader.SetDelimiters(",")
                Dim currentRow As String()
                While Not MyReader.EndOfData
                    Application.DoEvents()
                    Try
                        currentRow = MyReader.ReadFields()
                        With DataGridView1
                            .ColumnCount = 2
                            Dim row As String() = New String() {currentRow(0), currentRow(1)}
                            .Rows.Add(row)
                        End With

                    Catch ex As Microsoft.VisualBasic.
                                FileIO.MalformedLineException
                        MsgBox("Line " & ex.Message &
                        "is not valid and will be skipped.")
                    End Try
                End While
            End Using
        Catch ex As Exception

        End Try
    End Sub

---

If anyone could give hints on how to save data on arrarys that would be great because I want to plot graphs from the loaded csv data.

Thanks.

If you're going to read the file line by line then you can't really use an array, at least to begin with. You would use a collection instead, which will grow dynamically as you Add items.

You should start by defining a type that can store a single record. If your record contains two String values then your class might look something like this:

Code:

---

Public Class Thing
    Public Property Value1 As String
    Public Property Value2 As String
End Class

---

If the number and or type of the fields is different then vary your definition accordingly. Use more appropriate names as well.

You can then create a List(Of Thing) and use that to store your records. As you read a record, you create an instance, populate its properties and then Add it to the collection. When you're done reading, your collection can be used just like an array for the most part. If you specifically need an array then you can call ToArray on the collection to get one.

Thank you for your reply. But I am not sure how to implement your ideas.

Well, first things first, what would your type look like to represent a record?

My simple dataset looks like following:

Code:

---

date, distance
1,5
2,8
4,9
10,15

---

Thanks.

That's not what I asked. I said that you should start by defining a type to represent a single record and I gave you an example of what that might look like. What should that type look like for your data? What should the name of the class be? How many properties should it have? What should be the types of the properties? What should be the names of those properties?

Are you asking for this ?

It would look something like:

Code:

---

Public Class flow
    Public Property point As double
    Public Property distance As double
End Class

---

wait... CurrentRow IS an array... so why are you doing this:
Dim row As String() = New String() {currentRow(0), currentRow(1)}

You're taking an array, and sending each element to another array...

I don't understand what the problem is... ReadFeilds of the text file parser returns a string array...

So what's the problem?

jsut do this:

Code:

---

currentRow = MyReader.ReadFields()
With DataGridView1
    .Rows.Add(currentRow)
End With

---

You might even be able to do this:

Code:

---

With DataGridView1
    .Rows.Add(MyReader.ReadFields())
End With

---

now, if you need them to be doubles and not strings, then try this:

Code:

---

currentRow = MyReader.ReadFields()
With DataGridView1
    .Rows.Add(new Double() {cdbl(currentRow(0)), cdbl(currentRow(1))})
End With

---

Be sure to skip incomplete rows, and the header too...

-tg

The problem here is not with reading the data into datagridview1.

But I want to either use datagridview1 data to plot charts or directly read csv file in an array so that I can plot graphs.

For example to plot chart, I have something like this :

Code:

---

Dim xdat As Array
            Dim ydat As Array

            xdat = {0, 1, 2, 3, 4, 5}
            ydat = {5.5, 10.1, 11.3, 14, 15}

            chart.Show()

            chart.Chart1.Series(0).Points.DataBindXY(xdat, ydat)

            chart.Chart1.Series(0).ChartType = DataVisualization.Charting.SeriesChartType.Line

---

How can i replace xdat, ydat with the data in the Datagridview or data from csv ?

As mentioned earlier csv looks like following:

Code:

---

date, distance
1,5
2,8
4,9
10,15

---

I am coming from R programming background and it is so trivial to do such thing there but I am so stuck in this simple thing. I need to build an application so I am using vb.net.

Thanks.

Code:

---

'Outside the loop
Dim xLDat as new List(of Decimal)
dim yLDat as new List(Of Decimal)


'inside the loop while reading...
currentRow = MyReader.ReadFields()
xLDat.Add(cdec(currentRow(0)))
yLDat.Add(cdec(currentRow(1)))


'After the loop and done reading...
xDat = xLDat.ToArray
yDat = yLDat.ToArray

'Done

---

-tg

Techgnome,

Thank you so much. It works great.