c# - 使用 C# 将 csv 文件转换为 json

Question

我想知道是否有人编写了一个实用程序来使用 C# 将 CSV 文件转换为 Json。从上一个关于stackoverflow的问题中，我知道了这个不错的实用程序-https: //github.com/cparker15/csv-to-json，目前我打算参考它，但现有的C#实现会很有帮助！谢谢！

Answer 1

如果你可以使用System.Web.Extensions，这样的事情可以工作：

var csv = new List<string[]>(); // or, List<YourClass>
var lines = System.IO.File.ReadAllLines(@"C:\file.txt");
foreach (string line in lines)
    csv.Add(line.Split(',')); // or, populate YourClass          
string json = new 
    System.Web.Script.Serialization.JavaScriptSerializer().Serialize(csv);

您可能对 csv 文件有更复杂的解析要求，并且您可能有一个封装一行数据的类，但关键是一旦您拥有一组行，您就可以使用一行代码序列化为 JSON。

Answer 2

Cinchoo ETL - 一个开源库，只需几行代码即可轻松将 CSV 转换为 JSON

对于示例 CSV：

Id, Name, City
1, Tom, NY
2, Mark, NJ
3, Lou, FL
4, Smith, PA
5, Raj, DC

示例代码，

string csv = @"Id, Name, City
1, Tom, NY
2, Mark, NJ
3, Lou, FL
4, Smith, PA
5, Raj, DC
";

StringBuilder sb = new StringBuilder();
using (var p = ChoCSVReader.LoadText(csv)
    .WithFirstLineHeader()
    )
{
    using (var w = new ChoJSONWriter(sb))
        w.Write(p);
}

Console.WriteLine(sb.ToString());

输出 JSON：

[
 {
  "Id": "1",
  "Name": "Tom",
  "City": "NY"
 },
 {
  "Id": "2",
  "Name": "Mark",
  "City": "NJ"
 },
 {
  "Id": "3",
  "Name": "Lou",
  "City": "FL"
 },
 {
  "Id": "4",
  "Name": "Smith",
  "City": "PA"
 },
 {
  "Id": "5",
  "Name": "Raj",
  "City": "DC"
 }
]

小提琴示例：https ://dotnetfiddle.net/pclnsT

查看CodeProject文章以获得更多帮助。

更新： 如果您的 CSV 文件有重复的列名或没有名称，请使用以下步骤生成 JSON 文件

string csv = @"Id, Name, 
1, Tom, NY
2, Mark, NJ
3, Lou, FL
4, Smith, PA
5, Raj, DC
";

StringBuilder sb = new StringBuilder();
using (var p = ChoCSVReader.LoadText(csv)
    .WithField("Id", position: 1)
    .WithField("Name", position: 2)
    .WithField("City", position: 3)
    .WithFirstLineHeader(true)
    )
{
    using (var w = new ChoJSONWriter(sb))
        w.Write(p);
}

Console.WriteLine(sb.ToString());

小提琴示例：https ://dotnetfiddle.net/pP5Du6

免责声明：我是这个库的作者。

Answer 3

我使用了 Dictionary 并使用 newtonsoft 返回了 json

public string ConvertCsvFileToJsonObject(string path) 
{
    var csv = new List<string[]>();
    var lines = File.ReadAllLines(path);

    foreach (string line in lines)
        csv.Add(line.Split(','));

    var properties = lines[0].Split(',');

    var listObjResult = new List<Dictionary<string, string>>();

    for (int i = 1; i < lines.Length; i++)
    {
        var objResult = new Dictionary<string, string>();
        for (int j = 0; j < properties.Length; j++)
            objResult.Add(properties[j], csv[i][j]);

        listObjResult.Add(objResult);
    }

    return JsonConvert.SerializeObject(listObjResult); 
}

Answer 4

Install Nuget package NewtonSoft.Json
Add reference dll Microsoft.VisualBasic

using System.Linq;
using Newtonsoft.Json;
using Microsoft.VisualBasic.FileIO;
using System.IO;
using System;
using System.Collections.Generic;
using System.Globalization;

namespace Project
{
    public static class Program
    {
        public static void Main(string[] args)
        {
            string CSVpath = @"D:\New Folder\information.csv";
            string analyticsData = ReadFile(CSVpath);
        }

        private static string ReadFile(string filePath)
        {
            string payload = "";
            try
            {
                if (!string.IsNullOrWhiteSpace(filePath) && File.Exists(filePath) && Path.GetExtension(filePath).Equals(".csv", StringComparison.InvariantCultureIgnoreCase))
                {
                    string[] lines = File.ReadAllLines(filePath);

                    if (lines != null && lines.Length > 1)
                    {
                        var headers = GetHeaders(lines.First());
                        payload = GetPayload(headers, lines.Skip(1));
                    }
                }
            }
            catch (Exception exp)
            {
            }
            return payload;
        }

        private static IEnumerable<string> GetHeaders(string data)
        {
            IEnumerable<string> headers = null;

            if (!string.IsNullOrWhiteSpace(data) && data.Contains(','))
            {
                headers = GetFields(data).Select(x => x.Replace(" ", ""));
            }
            return headers;
        }

        private static string GetPayload(IEnumerable<string> headers, IEnumerable<string> fields)
        {
            string jsonObject = "";
            try
            {
                var dictionaryList = fields.Select(x => GetField(headers, x));
                jsonObject = JsonConvert.SerializeObject(dictionaryList);
            }
            catch (Exception ex)
            {
            }
            return jsonObject;
        }

        private static Dictionary<string, string> GetField(IEnumerable<string> headers, string fields)
        {
            Dictionary<string, string> dictionary = null;

            if (!string.IsNullOrWhiteSpace(fields))
            {
                var columns = GetFields(fields);

                if (columns != null && headers != null && columns.Count() == headers.Count())
                {
                    dictionary = headers.Zip(columns, (x, y) => new { x, y }).ToDictionary(item => item.x, item => item.y);
                }
            }
            return dictionary;
        }

        public static IEnumerable<string> GetFields(string line)
        {
            IEnumerable<string> fields = null;
            using (TextReader reader = new StringReader(line))
            {
                using (TextFieldParser parser = new TextFieldParser(reader))
                {
                    parser.TextFieldType = FieldType.Delimited; parser.SetDelimiters(","); fields = parser.ReadFields();
                }
            }
            return fields;
        }
    }
}

Answer 5

仅依赖于Newtonsoft.Json ，这是一个辅助方法，给定一组 CSV 行，第一个是标题。

    public static IEnumerable<JObject> CsvToJson(IEnumerable<string> csvLines)
    {
        var csvLinesList = csvLines.ToList();

        var header = csvLinesList[0].Split(',');
        for (int i = 1; i < csvLinesList.Count; i++)
        {
            var thisLineSplit = csvLinesList[i].Split(',');
            var pairedWithHeader = header.Zip(thisLineSplit, (h, v) => new KeyValuePair<string, string>(h, v));

            yield return new JObject(pairedWithHeader.Select(j => new JProperty(j.Key, j.Value)));
        }
    }

Answer 6

我使用ChoETL：

using ChoETL;
using System.IO;

public class FromCSVtoJSON
{
    public FromCSVtoJSON()
    {

    }

    public void convertFile(string inputFile, string outputFile)
    {
        using (var writer = new ChoJSONWriter(outputFile))
        {
            using (var reader = new ChoCSVReader(inputFile).WithFirstLineHeader())
            {
                writer.Write(reader);
            }
        }
    }
}

Answer 7

从同一个 SO 答案中，有一个指向这篇文章的链接。

CsvToJson 扩展方法

/// <summary>
/// Converts a CSV string to a Json array format.
/// </summary>
/// <remarks>First line in CSV must be a header with field name columns.</remarks>
/// <param name="value"></param>
/// <returns></returns>
public static string CsvToJson(this string value)
{
    // Get lines.
    if (value == null) return null;
    string[] lines = value.Split(new string[] { Environment.NewLine }, StringSplitOptions.RemoveEmptyEntries);
    if (lines.Length < 2) throw new InvalidDataException("Must have header line.");

    // Get headers.
    string[] headers = lines.First().SplitQuotedLine(new char[] { ',' }, false);

    // Build JSON array.
    StringBuilder sb = new StringBuilder();
    sb.AppendLine("[");
    for (int i = 1; i < lines.Length; i++)
    {
        string[] fields = lines[i].SplitQuotedLine(new char[] { ',', ' ' }, true, '"', false);
        if (fields.Length != headers.Length) throw new InvalidDataException("Field count must match header count.");
        var jsonElements = headers.Zip(fields, (header, field) => string.Format("{0}: {1}", header, field)).ToArray();
        string jsonObject = "{" + string.Format("{0}", string.Join(",", jsonElements)) + "}";
        if (i < lines.Length - 1)
            jsonObject += ",";
        sb.AppendLine(jsonObject);
    }
    sb.AppendLine("]");
    return sb.ToString();
}

在上面的扩展中调用的某些方法似乎存在问题（请参阅原始博客文章的评论），但它应该可以让您大部分时间到达那里。

编辑这是关于拆分 CSV 行的另一个 SO 答案。您可以使用建议的正则表达式解决方案之一来创建自己的SplitQuotedLine方法：

public static string SplitQuotedLine(this string value, char separator, bool quotes) {
    // Use the "quotes" bool if you need to keep/strip the quotes or something...
    var s = new StringBuilder();
    var regex = new Regex("(?<=^|,)(\"(?:[^\"]|\"\")*\"|[^,]*)");
    foreach (Match m in regex.Matches(value)) {
        s.Append(m.Value);
    }
    return s.ToString();
}

以上我没有测试，如有错误请见谅。

此外，似乎Zip 是一种 LINQ 扩展方法，因此可以解决该问题。

Answer 8

这是我的。它可以解析几个世纪以来的 9k CSV 记录。哈哈

class CSVTOJSON
{
    public string ConvertToJSON()
    {
        string json = string.Empty;
        string csv = string.Empty;

        using (StreamReader reader = new StreamReader("data.csv"))
        {
            csv = reader.ReadToEnd();
        }

        string[] lines = csv.Split(new string[] { "\n" }, System.StringSplitOptions.None);

        if (lines.Length > 1)
        {
            // parse headers
            string[] headers = lines[0].Split(',');

            StringBuilder sbjson = new StringBuilder();
            sbjson.Clear();
            sbjson.Append("[");

            // parse data
            for (int i = 1; i < lines.Length; i++)
            {
                if (string.IsNullOrWhiteSpace(lines[i])) continue;
                if (string.IsNullOrEmpty(lines[i])) continue;

                sbjson.Append("{");

                string[] data = lines[i].Split(',');

                for (int h = 0; h < headers.Length; h++)
                {
                    sbjson.Append(
                        $"\"{headers[h]}\": \"{data[h]}\"" + (h < headers.Length - 1 ? "," : null)
                    );
                }

                sbjson.Append("}" + (i < lines.Length - 1 ? "," : null));
            }

            sbjson.Append("]");

            json = sbjson.ToString();
        }

        return json;
    }
}

但它有效。

控制台日志：

Converting CSV to JSON
CSV has 9486 data
Total duration converting CSV to JSON: 00:00:00.0775373

Answer 9

试试这个并转换CSV为JSON对象：

public static List<object> CsvToJson( string body, string[] column ) {
    if ( string.IsNullOrEmpty( body ) ) return null;
    string[] rowSeparators = new string[] { "\r\n" };
    string[] rows = body.Split( rowSeparators, StringSplitOptions.None );
    body = null;
    if ( rows == null || ( rows != null && rows.Length == 0 ) ) return null;
    string[] cellSeparator = new string[] { "," };
    List<object> data = new List<object>( );
    int clen = column.Length;
    rows.Select( row => {
        if ( string.IsNullOrEmpty( row ) ) return row;
        string[] cells = row.Trim( ).Split( cellSeparator, StringSplitOptions.None );
        if ( cells == null ) return row;
        if ( cells.Length < clen ) return row;
        Dictionary<object, object> jrows = new Dictionary<object, object>( );
        for ( int i = 0; i < clen; i++ ) {
            jrows.Add( column[i], cells[i]?.Trim( ) );
        }
        data.Add( jrows );
        return row;
    } ).ToList( );
    rowSeparators = null; rows = null;
    cellSeparator = null;
    return data;
}

var data = CsvToJson("csv_input_str", new string[]{ "column_map" })
string jsonStr = new JavaScriptSerializer { MaxJsonLength = int.MaxValue }.Serialize( data );

Answer 10

确保在解析大型 csv 文件之前在 web.config 中添加以下内容。

 <system.web.extensions>
       <scripting>
           <webServices>
               <jsonSerialization maxJsonLength="50000000"/>
           </webServices>
       </scripting>
   </system.web.extensions>

Answer 11

尝试这个：

 StreamReader sr = new StreamReader(filePath);
 while ((line = sr.ReadLine()) != null)
 {
      //Console.WriteLine(line);
      string[] csv = line.Split(',');
      var dictionary = new Dictionary<string, string>();
      dictionary.Add("dispatching_base_number",csv[0]);
      dictionary.Add("available_vehicles", csv[1]);
      dictionary.Add("vehicles_in_trips", csv[2]);
      dictionary.Add("Cancellations", csv[3]);
      string jsonN = new System.Web.Script.Serialization.JavaScriptSerializer().Serialize(dictionary);
      Console.WriteLine("Sending message: {0}",jsonN);
 }

Answer 12

我寻找这个问题的答案最后我通过使用字典解决了它

public static void CreateJsonFromCSV()
{
    string path = "C:\\Users\\xx\\xx\\xx\\xx\\lang.csv";
    string textFilePath = path;
    const Int32 BufferSize = 128;

    using (var fileStream = File.OpenRead(textFilePath))
    using (var streamReader = new StreamReader(fileStream, Encoding.UTF8, true, BufferSize))
    {
        String line;
        Dictionary<string, string> jsonRow = new Dictionary<string, string>();

        while ((line = streamReader.ReadLine()) != null)
        {

            string[] parts = line.Split(',');

            string key_ = parts[0];
            string value = parts[1];


            if (!jsonRow.Keys.Contains(key_))
            {
                jsonRow.Add(key_, value );
            }

        }
        var json = new JavaScriptSerializer().Serialize(jsonRow);
        string path_ = "C:\\XX\\XX\\XX\\XX\\XX.csv";
        File.WriteAllText(path_, json);
    }

} 

Answer 13

首先，将 csv 文件加载到数据表中，并将其序列化为 Json 文档。它使用可以明智地解析 csv 的 OLEDB 提供程序，

感谢 Jim Scott，https://stackoverflow.com/a/1050278/6928056

由 K_B 提供，https: //stackoverflow.com/a/2979938/6928056

using System.Data;
using System.Data.OleDb;
using System.Globalization;
using System.IO;
using Newtonsoft.Json;

static string ConvertCsvToJson(string path, bool isFirstRowHeader)
{
    string header = isFirstRowHeader ? "Yes" : "No";

    string pathOnly = Path.GetDirectoryName(path);
    string fileName = Path.GetFileName(path);

    string sql = @"SELECT * FROM [" + fileName + "]";

    using(OleDbConnection connection = new OleDbConnection(
              @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + pathOnly + 
              ";Extended Properties=\"Text;HDR=" + header + "\""))
    using(OleDbCommand command = new OleDbCommand(sql, connection))
    using(OleDbDataAdapter adapter = new OleDbDataAdapter(command))
    {
        var dataTable = new DataTable();
        dataTable.Locale = CultureInfo.CurrentCulture;
        adapter.Fill(dataTable);
        return JsonConvert.SerializeObject(dataTable, Formatting.Indented);
    }
}

Answer 14

bc3tech 解决方案的小变化，即避免外部依赖（在 Newtonsoft.Json 上），而是使用 System.Text.Json（dotnet core 3+）

public static IEnumerable<string> CsvToJson(string fileName, char delim = '|')
{
    var lines = File.ReadLines(fileName); 
    var hdr = new List<string>(lines.First().Trim().Split(delim));
    foreach (var l in lines.Skip(1).Where(l => (l.Trim() != String.Empty))) 
    {
        var val = l.Trim().Split(delim);
        var ds = hdr.Zip(val, (k, v) => new { k, v }).ToDictionary(x => x.k, x => x.v);
        yield return JsonSerializer.Serialize(ds);
    }
}

Answer 15

将平面 csv 文件转换为简单 json 格式对象集合的简单方法。适用于第一行带有标题行的文件。这种方法的一部分是在 SO 的其他地方找到的。添加对 Microsoft.VisualBasic 的引用。

using Microsoft.VisualBasic.FileIO;
public static StringBuilder ReadCsv()
    {
        var path = @"X:\...\input.csv";
        using (TextFieldParser csvParser = new TextFieldParser(path))
        {
            csvParser.CommentTokens = new string[] { "#" };
            //Remember to use your own separator
            csvParser.SetDelimiters(new string[] { ";" });
            csvParser.HasFieldsEnclosedInQuotes = false;

            StringBuilder json = new StringBuilder();
            string[] colNames = new string[0];
            string[] fields = new string[0];

            json.Append("[");

            int counter = 0;
            while (!csvParser.EndOfData)
            {
                if (counter == 0)
                {
                    //Read properies' names
                    colNames = csvParser.ReadFields();
                    counter++;
                    Console.WriteLine($"{colNames.Length} columns detected!");
                }
                else
                {
                    // Read current line fields, pointer moves to the next line.
                    // Read the properties' values
                    fields = csvParser.ReadFields();

                    json.Append("{");

                    for (int i = 0; i < colNames.Length; i++)
                    {
                        json.Append($"\"{colNames[i]}\":{TryParse(fields[i])}");
                        if (i != colNames.Length - 1)
                        {
                            json.Append(",");
                        }
                    }
                    json.Append("},");
                    Console.WriteLine($"Writing record nr.: {counter}");
                    counter++;
                }
            }
            json.Length--; //Remove trailing comma
            json.Append("]");
            return json;
        }
    }

string TryParse(string s)
    {
        if (string.IsNullOrEmpty(s)) return "null";
        //Remember to set your decimal character here!
        if (s.Contains('.'))
        {
            double dResult;
            //This works on my computer, could be different on your machine
            if (double.TryParse(s, NumberStyles.AllowDecimalPoint,
                                CultureInfo.InvariantCulture, out dResult))
                return dResult.ToString(CultureInfo.InvariantCulture);
        }
        else
        {
            int intResult;
            if (int.TryParse(s, out intResult))
                return intResult.ToString(CultureInfo.InvariantCulture);
        }
        return "\"" + s + "\"";
    }

---

这应该为您提供一个简单的 json 对象列表。

Answer 16

如果您正在寻找仅限 C# 的解决方案，这可能对您有用。我最近遇到了同样的问题，并创建了这种方法来克服。

public static string ConvertToJsonStructure(string csvDataAsString, char delimiter = ',', bool hasHeaders = true)
    {
        var output = string.Empty;
        if (string.IsNullOrEmpty(csvDataAsString))
            return "{}";

        var rows = csvDataAsString.Split(new string[] { Environment.NewLine }, StringSplitOptions.None);
        var headers = hasHeaders ? rows[0].Split(delimiter) : null;
        var colCount = headers?.Length;
        var jsonStart = "{";
        var jsonEnd = "}";

        if (rows.Length > (1 + (hasHeaders ? 1 : 0)))
        {
            jsonStart = "[";
            jsonEnd = "]";
        }

        output = output + jsonStart;

        int startIndex = hasHeaders ? 1 : 0;

        for (int i = startIndex; i < rows.Length; i++)
        {
            var cols = rows[i].Split(delimiter);

            if (colCount == null)
                colCount = cols.Length;

            var tempJson = "{";

            for (int j = 0; j < colCount.Value; j++)
            {
                if (hasHeaders)
                    tempJson = tempJson + $"\"{headers[j]}\":";

                var isNumber = Regex.IsMatch(cols[j], @"^\d + $");
                var val = isNumber ? cols[j] : $"\"{cols[j]}\"";
                tempJson = tempJson + val;

                if (j < colCount.Value - 1)
                    tempJson = tempJson + ",";

            }

            tempJson = tempJson + "}";

            if (i < rows.Length - 1)
                tempJson = tempJson + ",";

            output = output + tempJson;
        }

        output = output + jsonEnd;

        return output;
    }
}

你需要将你的内容作为字符串传递给这个方法，你可以做这样的事情来读取你的 csv

var csvAsString = File.ReadAllText("TestCsv.csv");

        var result = CsvToJson.ConvertToJsonStructure(csvAsString);