Trouble loading CSV file into datagridview

Question

0.00/5 (No votes)

See more:

The code below I used so when a button is clicked, the contents of a CSV file are loaded into the DataGridView. However, when I click the button, only one line prints and the rest do not print even if I click it again.

I am unsure on what the problem is, some help would be appreciated

Thanks

What I have tried:

VB

Private Sub btnLoadDGVGeneral_Click(sender As Object, e As EventArgs) Handles btnLoadDGVGeneral.Click
    dataGVGeneral.Rows.Clear()
    Try
        'New Variable: fname, represents File Path of CSV as String
        Dim fname As String = "E:\SAT\Work.io\Work.io\bin\Debug\ListofTasks.csv"
        Dim reader As New StreamReader(fname, Encoding.Default)
        Dim sline As String = ""
        Dim colsexpected As Integer = 7
        Dim r As Integer = 0

        sline = reader.ReadLine
        Do
            sline = reader.ReadLine
            If sline Is Nothing Then Exit Do
            Dim details() As String = sline.Split(",")
            dataGVGeneral.Rows.Add()
            For i As Integer = 0 To 7
                dataGVGeneral.Rows(r).Cells(i).Value = details(i)
            Next
            r = r + 1
        Loop
        reader.Close()
    Catch ex As Exception
    End Try
End Sub

Posted 26-Jul-20 1:39am

Shaheer Rizwan

Updated 26-Jul-20 3:40am

Patrice T

v3

Add a Solution

Comments

[no name] 26-Jul-20 7:57am

I assume the first sline = reader.ReadLine before the loop is to skip the column header info in the csv. So the question: Are there really more than 1 line of data in the csv?

Shaheer Rizwan 26-Jul-20 7:59am

yes, there's actually 13 more lines in the CSV file. I've got no idea why it isnt printing the rest

[no name] 26-Jul-20 8:03am

So I suggest to use the debugger and step through the code.

[no name] 26-Jul-20 8:22am

What happens if you comment out the "try catch" stuff?

Shaheer Rizwan 26-Jul-20 8:49am

I ran it without all the try stuff and this came up https://imgur.com/a/a7hUv17

[no name] 26-Jul-20 9:04am

So it shows you details() length is 7. Unfortunatelly I don't see on what line. But anyway becuase you hard coded the loop "from 0 to 7" this would be a problem (the line in the csv does not have 8 fields.

Try something like this (I don't know VB)
For i As Integer = 0 To details.Length - 1

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

OriginalGriff · Answer 1 · 2020-07-26T02:01:00

Solution 1

Almost certainly, it's been hidden by your error handling:
Never "swallow" exceptions:

Catch ex As Exception
End Try

Report them to the user, log them, do something with them, or don't bother with Try ... Catch at all.

When you swallow an exception, you throw away all the information that helps you fix a problem - you even throw away the fact that there was a problem in the first place, so it shows up later as a more serious and harder to identify and fix problem.

And we can't tell what is happening here as a result - and even if we could, we couldn;t test it because we don't have any access to your data.

So, it's going to be up to you.
Fortunately, you have a tool available to you which will help you find out what is going on: the debugger. If you don't know how to use it then a quick Google for "Visual Studio debugger" should give you the info you need.

Put a breakpoint on the first line in the function, and run your code through the debugger. Then look at your code, and at your data and work out what should happen manually. Then single step each line checking that what you expected to happen is exactly what did. When it isn't, that's when you have a problem, and you can back-track (or run it again and look more closely) to find out why.

Sorry, but we can't do that for you - time for you to learn a new (and very, very useful) skill: debugging!

Posted 26-Jul-20 2:01am

OriginalGriff

v2

Comments

Shaheer Rizwan 26-Jul-20 8:04am

so... should I try something else except of Try? Im a bit of a noob when it comes to coding and its for an assignment so im stressing so sorry if I wasn't thorough with explaining my problem

[no name] 26-Jul-20 8:05am

Oooh so obvious and I don't see it :blush:. +5

Shaheer Rizwan 26-Jul-20 8:16am

well i ran the debugger and went through it, and i still cant figure it out

OriginalGriff 26-Jul-20 8:28am

It "went through it" because you swallow the exception. If you add a Catch block, that's saying "I know what I'm doing with this error, so don't worry about it" to the system. So it doesn't. Your app doesn't stop working, the debugger doesn't trigger a break for you. The error silently, and mysteriously slides away into the far distance so no one can see it. Your code goes wrong, and doesn't display what you expected it to, but you have no idea why.

So stop swallowing exceptions!

Put a breakpoint at the top of that method and single step your way through it. Almost certainly, it will "jump" from somewhere in that code to the Catch block - so you can look at the Exception object and see why it jumped there (you will already know from where it jumped).

Armed with that information, you should be able to work out why. But without it? Whistling in the dark ...

Shaheer Rizwan 26-Jul-20 8:44am

I ran it by removing the Try statements, and this came up: https://imgur.com/a/a7hUv17

Shaheer Rizwan 26-Jul-20 8:51am

Nvm I fixed it. Although I couldn't understand it at first it was actually very helpful. Thanks man

Shaheer Rizwan 26-Jul-20 8:53am

The main problem wasn't actually with the code (semi). First I removed the try statements, then I changed a column which was a combobox to a normal textbox and it worked. I'm just going to validate that column to only accept numbers now.

OriginalGriff 26-Jul-20 8:54am

You're welcome!

And ... stop swallowing exceptions - see how useful they can be? :laugh:

Shaheer Rizwan 26-Jul-20 8:55am

yeah I will :) lol