Go语言中JSON数据到CSV文件的转换教程与常见问题解析

[
  {
    "recordId": 101,
    "Date of joining": "2023-01-01",
    "Employee ID": "EMP001"
  },
  {
    "recordId": 102,
    "Date of joining": "2023-02-15",
    "Employee ID": "EMP002"
  }
]

type Json struct {
    RecordID int64  `json:"recordId"`
    DOJ      string `json:"Date of joining"`
    EmpID    string `json:"Employee ID"`
}

// 错误示例：尝试将 []interface{} 写入 CSV
/*
for _,obj := range d {
  var record []interface{} // 这里的类型是 []interface{}
  record = append(record, obj.RecordID)
  record = append(record, obj.DOJ)
  record = append(record, obj.EmpID)
  w.Write(record) // 这里会报错
}
*/

cannot use record (type []interface {}) as type []string in function argument

package main

import (
    "encoding/csv"
    "encoding/json"
    "fmt"
    "io/ioutil"
    "os"
    "strconv" // 引入 strconv 包用于类型转换
)

// 定义与JSON结构对应的Go结构体
type JsonRecord struct {
    RecordID int64  `json:"recordId"`
    DOJ      string `json:"Date of joining"`
    EmpID    string `json:"Employee ID"`
}

func main() {
    // 1. 读取JSON文件
    jsonFilePath := "./people.json"
    data, err := ioutil.ReadFile(jsonFilePath)
    if err != nil {
        fmt.Printf("Error reading JSON file %s: %v\n", jsonFilePath, err)
        os.Exit(1)
    }

    // 2. 反序列化JSON数据到Go结构体切片
    var records []JsonRecord
    err = json.Unmarshal(data, &records)
    if err != nil {
        fmt.Printf("Error unmarshalling JSON data: %v\n", err)
        os.Exit(1)
    }

    // 3. 创建或打开CSV文件
    csvFilePath := "./people.csv"
    f, err := os.Create(csvFilePath)
    if err != nil {
        fmt.Printf("Error creating CSV file %s: %v\n", csvFilePath, err)
        os.Exit(1)
    }
    defer f.Close() // 确保文件在函数结束时关闭

    // 4. 初始化CSV写入器
    w := csv.NewWriter(f)

    // 可选：写入CSV文件头
    header := []string{"RecordID", "Date of Joining", "Employee ID"}
    if err := w.Write(header); err != nil {
        fmt.Printf("Error writing CSV header: %v\n", err)
        os.Exit(1)
    }

    // 5. 遍历JSON数据并写入CSV
    for _, obj := range records {
        var record []string // 定义 []string 类型的切片用于存储CSV行数据

        // 将 int64 类型的 RecordID 转换为字符串
        record = append(record, strconv.FormatInt(obj.RecordID, 10))
        record = append(record, obj.DOJ)
        record = append(record, obj.EmpID)

        // 写入CSV行
        if err := w.Write(record); err != nil {
            fmt.Printf("Error writing record to CSV: %v\n", err)
            os.Exit(1)
        }
    }

    // 6. 刷新CSV写入器，确保所有缓冲数据写入文件
    w.Flush()
    if err := w.Error(); err != nil {
        fmt.Printf("Error flushing CSV writer: %v\n", err)
        os.Exit(1)
    }

    fmt.Printf("Successfully converted JSON from %s to CSV in %s\n", jsonFilePath, csvFilePath)
}