Loading a .csv file into dictionary, I keep getting the error "cannot convert from 'string[]' to 'string'"

Question

I've used streamreader to read in a .csv file, then i need to split the values and put them into a dictionary. so far i have:

namespace WindowsFormsApplication2
{
public partial class Form1 : Form
{
Dictionary<string, string> dict = new Dictionary<string, string>();   
    public Form1()
    {
        InitializeComponent();
    }
    private void Form1_Load(object sender, EventArgs e)
    {
        using (StreamReader reader = new StreamReader("textwords0.csv"))
        {
            string line;
            while ((line = reader.ReadLine()) != null)
            {
                string[] parts = line.Split(',');
                dict.Add(parts[0], parts[1]);
            }
        }
    }

I keep getting the error "cannot convert from 'string[]' to 'string'" but cant work out how to fix it.

Thanks in advance!

update: ...I accidentally left the csv file open and its working now, sorry for wasting time guys thought i had a different spreadsheet open, some very useful advice though thanks for all the help!

Not sure if you solved this yet, but are you sure you are getting the exception you wrote in the question? I just ran this on some random data, and it worked just fine — psubsee2003, Mar 21 '12 at 01:20
Use a [CsvParser](https://github.com/JoshClose/CsvHelper), there are pretty good 3rd parties that take care of edge cases you haven't even thought of. — Yuval Itzchakov, May 24 '15 at 13:28

score 45 · Accepted Answer · edited Sep 06 '15 at 01:24

45

If you're using .NET 4.0, the following is really succinct and should accomplish the same thing:

var dict = File.ReadLines("textwords0.csv").Select(line => line.Split(',')).ToDictionary(line => line[0], line => line[1]);

edited Sep 06 '15 at 01:24

Shiva

20,575
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answered Mar 20 '12 at 17:02

Taylor Southwick

1,456
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2

not sure this would work if you have data with ',' in them. you need csv parser here. – nakhli Mar 20 '12 at 17:05
4

this is fragile as the value could be wrapped in quotes if it contains a comma `("this is, a value")` - the value will be split in half – James Shuttler Mar 20 '12 at 17:06
1

That's true about it not checking if the comma is in a quote or the data, but @jesusjuice doesn't seem worried about that. – Taylor Southwick Mar 20 '12 at 17:14
1

You could try using a regex like the following: var rgx = new System.Text.RegularExpressions.Regex("\"(.*?)\"|,"); rgx.Split("open,\"drive, over the , moon\",kriston"); – ermagana Aug 23 '13 at 16:07
This fails if the CSV file has fields that contain commas enclosed in quotes, which is a very common scenario. Ex: `"This is 1st column, that also has a comma inside, so excel encloses column value in quotes",This is 2nd column no comma inside.` – Shiva Sep 06 '15 at 01:26

score 0 · Answer 2 · answered Mar 20 '12 at 17:19

0

the error is actually because of the ',' you are inputting. It needs an "array" of characters to split from. Here is an example method of splitting using string.split.

string[] parts = line.Split(new string[] { "," }, StringSplitOptions.None);

Hope this helps. this is presuming this is the line the error is coming from as you havn't specified.

answered Mar 20 '12 at 17:19

Skintkingle

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apparently its line 33 which is the last }. I'm fairly new to programming in general so finding this slightly confusing. Thanks! – jesusjuice Mar 20 '12 at 17:35

Loading a .csv file into dictionary, I keep getting the error "cannot convert from 'string[]' to 'string'"

2 Answers2

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