C#.NET下转换泛型列表为JSON格式

 

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Text;

using System.Data;

using System.Data.Common;

using System.Collections;

using System.Reflection;



namespace LearningAspNet.JSON示例

{

    public class jsonCovert

    {

        /// <summary>

/// List转成json 

/// </summary>

/// <typeparam name="T"></typeparam>

/// <param name="jsonName"></param>

/// <param name="list"></param>

/// <returns></returns>

public  string ListToJson<T>(IList<T> list, string jsonName)

{

 StringBuilder Json = new StringBuilder();

 if (string.IsNullOrEmpty(jsonName))

  jsonName = list[0].GetType().Name;

 Json.Append("{\"" + jsonName + "\":[");

 if (list.Count > 0)

 {

  for (int i = 0; i < list.Count; i++)

  {

   T obj = Activator.CreateInstance<T>();

   PropertyInfo[] pi = obj.GetType().GetProperties();

   Json.Append("{");

   for (int j = 0; j < pi.Length; j++)

   {

    Type type = pi[j].GetValue(list[i], null).GetType();

    Json.Append("\"" + pi[j].Name.ToString() + "\":" + StringFormat(pi[j].GetValue(list[i], null).ToString(), type));



    if (j < pi.Length - 1)

    {

     Json.Append(",");

    }

   }

   Json.Append("}");

   if (i < list.Count - 1)

   {

    Json.Append(",");

   }

  }

 }

 Json.Append("]}");

 return Json.ToString();

}



/// <summary>

/// List转成json 

/// </summary>

/// <typeparam name="T"></typeparam>

/// <param name="list"></param>

/// <returns></returns>

public  string ListToJson<T>(IList<T> list)

{

 object obj = list[0];

 return ListToJson<T>(list, obj.GetType().Name);

}



/// <summary> 

/// 对象转换为Json字符串 

/// </summary> 

/// <param name="jsonObject">对象</param> 

/// <returns>Json字符串</returns> 

public  string ToJson(object jsonObject)

{

 string jsonString = "{";

 PropertyInfo[] propertyInfo = jsonObject.GetType().GetProperties();

 for (int i = 0; i < propertyInfo.Length; i++)

 {

  object objectValue = propertyInfo[i].GetGetMethod().Invoke(jsonObject, null);

  string value = string.Empty;

  if (objectValue is DateTime || objectValue is Guid || objectValue is TimeSpan)

  {

   value = "'" + objectValue.ToString() + "'";

  }

  else if (objectValue is string)

  {

   value = "'" + ToJson(objectValue.ToString()) + "'";

  }

  else if (objectValue is IEnumerable)

  {

   value = ToJson((IEnumerable)objectValue);

  }

  else

  {

   value = ToJson(objectValue.ToString());

  }

  jsonString += "\"" + ToJson(propertyInfo[i].Name) + "\":" + value + ",";

 }

 jsonString.Remove(jsonString.Length - 1, jsonString.Length);

 return jsonString + "}";

}



/// <summary> 

/// 对象集合转换Json 

/// </summary> 

/// <param name="array">集合对象</param> 

/// <returns>Json字符串</returns> 

public  string ToJson(IEnumerable array)

{

 string jsonString = "[";

 foreach (object item in array)

 {

  jsonString += ToJson(item) + ",";

 }

 jsonString.Remove(jsonString.Length - 1, jsonString.Length);

 return jsonString + "]";

}



/// <summary> 

/// 普通集合转换Json 

/// </summary> 

/// <param name="array">集合对象</param> 

/// <returns>Json字符串</returns> 

public  string ToArrayString(IEnumerable array)

{

 string jsonString = "[";

 foreach (object item in array)

 {

  jsonString = ToJson(item.ToString()) + ",";

 }

 jsonString.Remove(jsonString.Length - 1, jsonString.Length);

 return jsonString + "]";

}



/// <summary> 

/// Datatable转换为Json 

/// </summary> 

/// <param name="table">Datatable对象</param> 

/// <returns>Json字符串</returns> 

public  string ToJson(DataTable dt)

{

 StringBuilder jsonString = new StringBuilder();

 jsonString.Append("[");

 DataRowCollection drc = dt.Rows;

 for (int i = 0; i < drc.Count; i++)

 {

  jsonString.Append("{");

  for (int j = 0; j < dt.Columns.Count; j++)

  {

   string strKey = dt.Columns[j].ColumnName;

   string strValue = drc[i][j].ToString();

   Type type = dt.Columns[j].DataType;

   jsonString.Append("\"" + strKey + "\":");

   strValue = StringFormat(strValue, type);

   if (j < dt.Columns.Count - 1)

   {

    jsonString.Append(strValue + ",");

   }

   else

   {

    jsonString.Append(strValue);

   }

  }

  jsonString.Append("},");

 }

 jsonString.Remove(jsonString.Length - 1, 1);

 jsonString.Append("]");

 return jsonString.ToString();

}



/// <summary>

/// DataTable转成Json 

/// </summary>

/// <param name="jsonName"></param>

/// <param name="dt"></param>

/// <returns></returns>

public  string ToJson(DataTable dt, string jsonName)

{

 StringBuilder Json = new StringBuilder();

 if (string.IsNullOrEmpty(jsonName))

  jsonName = dt.TableName;

 Json.Append("{\"" + jsonName + "\":[");

 if (dt.Rows.Count > 0)

 {

  for (int i = 0; i < dt.Rows.Count; i++)

  {

   Json.Append("{");

   for (int j = 0; j < dt.Columns.Count; j++)

   {

    Type type = dt.Rows[i][j].GetType();

    Json.Append("\"" + dt.Columns[j].ColumnName.ToString() + "\":" + StringFormat(dt.Rows[i][j].ToString(), type));

    if (j < dt.Columns.Count - 1)

    {

     Json.Append(",");

    }

   }

   Json.Append("}");

   if (i < dt.Rows.Count - 1)

   {

    Json.Append(",");

   }

  }

 }

 Json.Append("]}");

 return Json.ToString();

}



/// <summary> 

/// DataReader转换为Json 

/// </summary> 

/// <param name="dataReader">DataReader对象</param> 

/// <returns>Json字符串</returns> 

public  string ToJson(DbDataReader dataReader)

{

 StringBuilder jsonString = new StringBuilder();

 jsonString.Append("[");

 while (dataReader.Read())

 {

  jsonString.Append("{");

  for (int i = 0; i < dataReader.FieldCount; i++)

  {

   Type type = dataReader.GetFieldType(i);

   string strKey = dataReader.GetName(i);

   string strValue = dataReader[i].ToString();

   jsonString.Append("\"" + strKey + "\":");

   strValue = StringFormat(strValue, type);

   if (i < dataReader.FieldCount - 1)

   {

    jsonString.Append(strValue + ",");

   }

   else

   {

    jsonString.Append(strValue);

   }

  }

  jsonString.Append("},");

 }

 dataReader.Close();

 jsonString.Remove(jsonString.Length - 1, 1);

 jsonString.Append("]");

 return jsonString.ToString();

}



/// <summary> 

/// DataSet转换为Json 

/// </summary> 

/// <param name="dataSet">DataSet对象</param> 

/// <returns>Json字符串</returns> 

public  string ToJson(DataSet dataSet)

{

 string jsonString = "{";

 foreach (DataTable table in dataSet.Tables)

 {

  jsonString += "\"" + table.TableName + "\":" + ToJson(table) + ",";

 }

 jsonString = jsonString.TrimEnd(',');

 return jsonString + "}";

}



/// <summary>

/// 过滤特殊字符

/// </summary>

/// <param name="s"></param>

/// <returns></returns>

public  string String2Json(String s)

{

 StringBuilder sb = new StringBuilder();

 for (int i = 0; i < s.Length; i++)

 {

  char c = s.ToCharArray()[i];

  switch (c)

  {

   case '\"':

    sb.Append("\\\""); break;

   case '\\':

    sb.Append("\\\\"); break;

   case '/':

    sb.Append("\\/"); break;

   case '\b':

    sb.Append("\\b"); break;

   case '\f':

    sb.Append("\\f"); break;

   case '\n':

    sb.Append("\\n"); break;

   case '\r':

    sb.Append("\\r"); break;

   case '\t':

    sb.Append("\\t"); break;

   default:

    sb.Append(c); break;

  }

 }

 return sb.ToString();

}



/// <summary>

/// 格式化字符型、日期型、布尔型

/// </summary>

/// <param name="str"></param>

/// <param name="type"></param>

/// <returns></returns>

public  string StringFormat(string str, Type type)

{

 if (type == typeof(string))

 {

  str = String2Json(str);

  str = "\"" + str + "\"";

 }

 else if (type == typeof(DateTime))

 {

  str = "\"" + str + "\"";

 }

 else if (type == typeof(bool))

 {

  str = str.ToLower();

 }

 return str;

}



 



    }

}