Write function from encoding/csv pkg stops writting in csv file

Question

I'm trying to extract the names of .txt files in a folder.
But I encounter an issue where the write function from encoding/csv stop writing in the csv file I initialize.
The code is as follow.

import (
        "encoding/csv"
        "io/ioutil"
        "log"
        "os"
        "strings"
)

func Extract() error {

    //read folder
    AllFiles, err := ioutil.ReadDir("./folder")
    if err != nil {
        return err
    }

    //create csv file
    SupportCsv, err := os.Create("csvfile.csv")
    if err != nil {
        return err
    }

    WriterSupport := csv.NewWriter(SupportCsv)

    for _, file := range AllFiles {

        res := []string{"test", file.Name()}

        log.Println(res)

        //write in csv file
        err = WriterSupport.Write(res)
        if err != nil {
            return err
        }
    }
return nil
}

I have ~300 .txt file in my folder.
The log.Println prints everything so the issue must be with the Write function.
In return the csv file as less file name and the last name is not written entirely.
Moreover, when i change the number of letter on "test" string in res, the csv file as in return more or less file name in it.
Write returns no error.

Also, don't forget to close your file: defer SupportCsv.Close(). — jub0bs
– jub0bs, Commented Jul 23, 2021 at 10:11

jub0bs · Accepted Answer · 2021-07-23 10:42:24Z

3

Looks like you have missed WriterSupport.Flush() after the write. All you need to do is to defer the Flush() to make sure that it is executed. Better after creating WriterSupport := csv.NewWriter(SupportCsv)

WriterSupport := csv.NewWriter(SupportCsv)
defer WriterSupport.Flush()

edited Jul 23, 2021 at 10:42

jub0bs

67.2k27 gold badges198 silver badges200 bronze badges

answered Jul 23, 2021 at 10:27

Shailesh Suryawanshi

1,2808 silver badges13 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

jub0bs Over a year ago

No, flushing within the loop most likely isn't what you want. Do it once after of the loop. Better yet: defer WriterSupport.Flush() after creating the writer.

Shailesh Suryawanshi Over a year ago

@jub0bs I agree that the flushing within loop is not the right way of doing this. Updated the answer.

Collectives™ on Stack Overflow

Write function from encoding/csv pkg stops writting in csv file

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related