operations on csv file, read and write CSV file

Introduction

CSV (Comma Separated Value) files are a common way of storing data that can be read by various software applications. CSV files are plain text files that contain a list of data records separated by commas. Go provides an easy and efficient way to read and write CSV files.

In this article, we will learn how to read and write CSV files in Go.

Prerequisites

Before we start, we need to have Go installed on our system. We can download and install the latest version of Go from the official Go website.

Reading CSV Files

Go provides a built-in package called "encoding/csv" that allows us to read CSV files. We can use this package to read a CSV file and store its contents in a 2D slice.

Here is an example of how to read a CSV file:

package main

import (
    "encoding/csv"
    "fmt"
    "os"
)

func main() {
    // Open the CSV file
    file, err := os.Open("data.csv")
    if err != nil {
        fmt.Println("Error:", err)
        return
    }
    defer file.Close()

    // Create a new reader
    reader := csv.NewReader(file)

    // Read all the records
    records, err := reader.ReadAll()
    if err != nil {
        fmt.Println("Error:", err)
        return
    }

    // Print the records
    fmt.Println(records)
}

In this example, we first open the CSV file using the os.Open() function. If there is an error, we print it and return. Next, we create a new csv.Reader and pass the file object to it. Finally, we call the ReadAll() function to read all the records from the CSV file and store them in a 2D slice called records.

Writing CSV Files

To write data to a CSV file, we can use the same encoding/csv package. We can create a new csv.Writer object and write data to it using the Write() method. We can also use the Flush() method to flush the data to the file.

Here is an example of how to write data to a CSV file:

package main

import (
    "encoding/csv"
    "fmt"
    "os"
)

func main() {
    // Create a new file
    file, err := os.Create("data.csv")
    if err != nil {
        fmt.Println("Error:", err)
        return
    }
    defer file.Close()

    // Create a new writer
    writer := csv.NewWriter(file)

    // Write some records
    records := [][]string{
        {"John", "Doe", "25"},
        {"Jane", "Doe", "30"},
        {"Tom", "Smith", "35"},
    }
    for _, record := range records {
        err := writer.Write(record)
        if err != nil {
            fmt.Println("Error:", err)
            return
        }
    }

    // Flush the data to the file
    writer.Flush()
}

In this example, we first create a new file using the os.Create() function. If there is an error, we print it and return. Next, we create a new csv.Writer and pass the file object to it. We then write some records to the writer using the Write() method. Finally, we call the Flush() method to flush the data to the file.

Conclusion

In this article, we learned how to read and write CSV files in Go. Go provides a built-in package called encoding/csv that makes it easy to read and write CSV files. We can use the csv.Reader object to read CSV data.

I hope this helps, you!!

More such articles:

https://medium.com/techwasti

https://www.youtube.com/channel/UCiTaHm1AYqMS4F4L9zyO7qA

https://www.techwasti.com/

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Read and Write CSV file in go language!

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Introduction

Prerequisites

Reading CSV Files

Writing CSV Files

Conclusion

Command Palette

Comments

go-language

More from this blog

Introduction

Prerequisites

Reading CSV Files

Writing CSV Files

Conclusion