C#实现Json转DataTable并导出Excel的方法示例

素材狗 2023-01-20 19:30:01 文章分类：C#/.NET开发点击数：8次

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这篇文章主要介绍了C#实现Json转DataTable并导出Excel的方法,结合实例形式总结分析了Json转换DataTable,以及DataTable导出Excel相关操作技巧,需要的朋友可以参考下

本文实例讲述了C#实现Json转DataTable并导出Excel的方法。分享给大家供大家参考，具体如下：

需求：有一个log文件，需要整理成Excel，日志文件里面的数据都是json字符串

思路是，把Json字符串转换成DataTable，然后导出到Excel

在网上找了一些资料，整理了以下三种类型的Json

一、Json转换DataTable

1.处理简单Json：

[{"mac":"20:f1:7c:c5:cd:80","rssi":"-86","ch":"9"},{"mac":"20:f1:7c:c5:cd:85","rssi":"-91","ch":"9"}]


/// <summary>
/// Json 字符串 转换为 DataTable数据集合
/// </summary>
/// <param name="json"></param>
/// <returns></returns>
public static DataTable ToDataTableTwo(string json)
{
  DataTable dataTable = new DataTable(); //实例化
  DataTable result;
  try
  {
    JavaScriptSerializer javaScriptSerializer = new JavaScriptSerializer();
    javaScriptSerializer.MaxJsonLength = Int32.MaxValue; //取得最大数值
    ArrayList arrayList = javaScriptSerializer.Deserialize<ArrayList>(json);
    if (arrayList.Count > 0)
    {
      foreach (Dictionary<string, object> dictionary in arrayList)
      {
        if (dictionary.Keys.Count<string>() == 0)
        {
          result = dataTable;
          return result;
        }
        //Columns
        if (dataTable.Columns.Count == 0)
        {
          foreach (string current in dictionary.Keys)
          {
            dataTable.Columns.Add(current, dictionary[current].GetType());
          }
        }
        //Rows
        DataRow dataRow = dataTable.NewRow();
        foreach (string current in dictionary.Keys)
        {
          dataRow[current] = dictionary[current];
        }
        dataTable.Rows.Add(dataRow); //循环添加行到DataTable中
      }
    }
  }
  catch
  {
  }
  result = dataTable;
  return result;
}

2.处理复杂Json

[{"id":"00e58d51","data":[{"mac":"20:f1:7c:c5:cd:80","rssi":"-86","ch":"9"},{"mac":"20:f1:7c:c5:cd:85","rssi":"-91","ch":"9"}]},
{"id":"00e58d53","data":[{"mac":"bc:d1:77:8e:26:78","rssi":"-94","ch":"11"},{"mac":"14:d1:1f:3e:bb:ac","rssi":"-76","ch":"11"},{"mac":"20:f1:7c:d4:05:41","rssi":"-86","ch":"12"}]}]


/// <summary>
/// Json 字符串 转换为 DataTable数据集合
/// </summary>
/// <param name="json"></param>
/// <returns></returns>
public static DataTable ToDataTable(string json)
{
  DataTable dataTable = new DataTable(); //实例化
  DataTable result;
  try
  {
    JavaScriptSerializer javaScriptSerializer = new JavaScriptSerializer();
    javaScriptSerializer.MaxJsonLength = Int32.MaxValue; //取得最大数值
    ArrayList arrayList = javaScriptSerializer.Deserialize<ArrayList>(json);
    if (arrayList.Count > 0)
    {
      foreach (Dictionary<string, object> dictionary in arrayList)
      {
        if (dictionary.Keys.Count<string>() == 0)
        {
          result = dataTable;
          return result;
        }
        //Columns
        if (dataTable.Columns.Count == 0)
        {
          foreach (string current in dictionary.Keys)
          {
            if (current != "data")
              dataTable.Columns.Add(current, dictionary[current].GetType());
            else
            {
              ArrayList list = dictionary[current] as ArrayList;
              foreach (Dictionary<string, object> dic in list)
              {
                foreach (string key in dic.Keys)
                {
                  dataTable.Columns.Add(key, dic[key].GetType());
                }
                break;
              }
            }
          }
        }
        //Rows
        string root = "";
        foreach (string current in dictionary.Keys)
        {
          if (current != "data")
            root = current;
          else
          {
            ArrayList list = dictionary[current] as ArrayList;
            foreach (Dictionary<string, object> dic in list)
            {
              DataRow dataRow = dataTable.NewRow();
              dataRow[root] = dictionary[root];
              foreach (string key in dic.Keys)
              {
                dataRow[key] = dic[key];
              }
              dataTable.Rows.Add(dataRow);
            }
          }
        }
      }
    }
  }
  catch
  {
  }
  result = dataTable;
  return result;
}

3.处理不规则Json，因为列并不确定，所以直接定义列，不动态生成

[{"id":"00e58d53","data":[{"mac":"34:b3:54:89:86:64","rssi":"-86","ch":"13"},{"mac":"50:bd:5f:02:80:44","rssi":"-90","ch":"1"}]},
{"id":"00ccda81","data":[{"mac":"bc:46:99:4e:96:c8","rssi":"-92","ch":"1"},{"mac":"bc:3a:ea:fc:77:6c","rssi":"-93","ch":"6","ds":"Y","essid":"vienna hotel WIFI"}]}]


/// <summary>
/// Json 字符串 转换为 DataTable数据集合
/// </summary>
/// <param name="json"></param>
/// <returns></returns>
public static DataTable ToDataTable(string json)
{
  DataTable dataTable = new DataTable(); //实例化
  DataTable result;
  try
  {
    dataTable.Columns.Add("id");
    dataTable.Columns.Add("mac");
    dataTable.Columns.Add("rssi");
    dataTable.Columns.Add("ch");
    dataTable.Columns.Add("ts");
    dataTable.Columns.Add("tmc");
    dataTable.Columns.Add("tc");
    dataTable.Columns.Add("ds");
    dataTable.Columns.Add("essid");
    JavaScriptSerializer javaScriptSerializer = new JavaScriptSerializer();
    javaScriptSerializer.MaxJsonLength = Int32.MaxValue; //取得最大数值
    ArrayList arrayList = javaScriptSerializer.Deserialize<ArrayList>(json);
    if (arrayList.Count > 0)
    {
      foreach (Dictionary<string, object> dictionary in arrayList)
      {
        if (dictionary.Keys.Count<string>() == 0)
        {
          result = dataTable;
          return result;
        }//Rows
        string root = "";
        foreach (string current in dictionary.Keys)
        {
          if (current != "data")
            root = current;
          else
          {
            ArrayList list = dictionary[current] as ArrayList;
            foreach (Dictionary<string, object> dic in list)
            {
              DataRow dataRow = dataTable.NewRow();
              dataRow[root] = dictionary[root];
              foreach (string key in dic.Keys)
              {
                dataRow[key] = dic[key];
              }
              dataTable.Rows.Add(dataRow);
            }
          }
        }
      }
    }
  }
  catch
  {
  }
  result = dataTable;
  return result;
}

二、导出Excel


/// <summary>
/// 导出Excel
/// </summary>
/// <param name="table"></param>
/// <param name="file"></param>
public void dataTableToCsv(DataTable table, string file)
{
  string title = "";
  FileStream fs = new FileStream(file, FileMode.OpenOrCreate);
  StreamWriter sw = new StreamWriter(new BufferedStream(fs), System.Text.Encoding.Default);
  for (int i = 0; i < table.Columns.Count; i++)
  {
    title += table.Columns[i].ColumnName + "\t"; //栏位：自动跳到下一单元格
  }
  title = title.Substring(0, title.Length - 1) + "\n";
  sw.Write(title);
  foreach (DataRow row in table.Rows)
  {
    string line = "";
    for (int i = 0; i < table.Columns.Count; i++)
    {
      line += row[i].ToString().Trim() + "\t"; //内容：自动跳到下一单元格
    }
    line = line.Substring(0, line.Length - 1) + "\n";
    sw.Write(line);
  }
  sw.Close();
  fs.Close();
}

三、调用实现，数据导出到Excel


protected void Button1_Click(object sender, EventArgs e)
{
  string str = File.ReadAllText(@"C:\Users\Admin\Desktop\json.txt");
  DataTable dt = ToDataTable(str);
  this.dataTableToCsv(dt, @"E:\json.xls"); //调用函数
}