using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using Newtonsoft.Json;
using System.Data;
namespace VeryCodes.Common
{
/// <summary>
/// Json处理类
/// </summary>
public class JsonHelper
{
/// <summary>
/// 序列化数据为Json数据格式.
/// </summary>
/// <param name="value">The value.</param>
/// <returns></returns>
public static string Serialize(object value)
{
Type type = value.GetType();
Newtonsoft.Json.JsonSerializer json = new Newtonsoft.Json.JsonSerializer();
json.NullValueHandling = NullValueHandling.Ignore;
json.ObjectCreationHandling = Newtonsoft.Json.ObjectCreationHandling.Replace;
json.MissingMemberHandling = Newtonsoft.Json.MissingMemberHandling.Ignore;
json.ReferenceLoopHandling = ReferenceLoopHandling.Ignore;
if (type == typeof(DataRow))
json.Converters.Add(new DataRowConverter());
else if (type == typeof(DataTable))
json.Converters.Add(new DataTableConverter());
else if (type == typeof(DataSet))
json.Converters.Add(new DataSetConverter());
StringWriter sw = new StringWriter();
Newtonsoft.Json.JsonTextWriter writer = new JsonTextWriter(sw);
//writer.Formatting = Formatting.Indented;
writer.Formatting = Formatting.None;
writer.QuoteChar = '"';
json.Serialize(writer, value);
string output = sw.ToString();
writer.Close();
sw.Close();
return output;
}
/// <summary>
/// 反序列化Json数据格式.
/// </summary>
/// <param name="jsonText">The json text.</param>
/// <param name="valueType">Type of the value.</param>
/// <returns></returns>
public static object Deserialize(string jsonText, Type valueType)
{
Newtonsoft.Json.JsonSerializer json = new Newtonsoft.Json.JsonSerializer();
json.NullValueHandling = Newtonsoft.Json.NullValueHandling.Ignore;
json.ObjectCreationHandling = Newtonsoft.Json.ObjectCreationHandling.Replace;
json.MissingMemberHandling = Newtonsoft.Json.MissingMemberHandling.Ignore;
json.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Ignore;
StringReader sr = new StringReader(jsonText);
Newtonsoft.Json.JsonTextReader reader = new JsonTextReader(sr);
object result = json.Deserialize(reader, valueType);
reader.Close();
return result;
}
/// <summary>
/// 遍历DataTable的行和列生成Json，可控制性较差
/// </summary>
/// <param name="dt"></param>
/// <returns></returns>
public static string DataTable2Json(DataTable dt)
{
StringBuilder jsonBuilder = new StringBuilder();
jsonBuilder.Append("{\"");
jsonBuilder.Append(dt.TableName);
jsonBuilder.Append("\":[");
for (int i = 0; i < dt.Rows.Count; i++)
{
jsonBuilder.Append("{");
for (int j = 0; j < dt.Columns.Count; j++)
{
jsonBuilder.Append("\"");
jsonBuilder.Append(dt.Columns[j].ColumnName);
jsonBuilder.Append("\":\"");
jsonBuilder.Append(dt.Rows[i][j].ToString());
jsonBuilder.Append("\",");
}
jsonBuilder.Remove(jsonBuilder.Length - 1, 1);
jsonBuilder.Append("},");
}
jsonBuilder.Remove(jsonBuilder.Length - 1, 1);
jsonBuilder.Append("]");
jsonBuilder.Append("}");
return jsonBuilder.ToString();
}
/// <summary>
/// 遍历DataTable的行和列生成Json，控制数据列，专门为FlexiGrid提供便捷的数据源生成
/// </summary>
/// <param name="dt">DataTable对象</param>
/// <param name="cols">Json中的数据列</param>
/// <returns></returns>
public static string Json4FlexiGrid(DataTable dt, string cols)
{
StringBuilder jsonBuilder = new StringBuilder();
string[] colarr = cols.Split(',');
if (dt.Rows.Count > 0)
{
for (int i = 0; i < dt.Rows.Count; i++)
{
jsonBuilder.Append("{");
jsonBuilder.Append("\"id\":");
jsonBuilder.Append("\"");
jsonBuilder.Append(dt.Rows[i]["ID"].ToString());
jsonBuilder.Append("\",\"cell\":[");
foreach (string col in colarr)
{
jsonBuilder.Append("\"");
jsonBuilder.Append(dt.Rows[i][col].ToString());
jsonBuilder.Append("\",");
}
jsonBuilder.Remove(jsonBuilder.Length - 1, 1);
jsonBuilder.Append("]},");
}
jsonBuilder.Remove(jsonBuilder.Length - 1, 1);
}
return jsonBuilder.ToString();
}
}
/// <summary>
/// Converts a <see cref="DataRow"/> object to and from JSON.
/// </summary>
public class DataRowConverter : JsonConverter
{
/// <summary>
/// Writes the JSON representation of the object.
/// </summary>
/// <param name="writer">The <see cref="JsonWriter"/> to write to.</param>
/// <param name="dataRow">The data row.</param>
/// <param name="ser">The JsonSerializer 对象.</param>
public override void WriteJson(JsonWriter writer, object dataRow, JsonSerializer ser)
{
DataRow row = dataRow as DataRow;
writer.WriteStartObject();
foreach (DataColumn column in row.Table.Columns)
{
writer.WritePropertyName(column.ColumnName);
ser.Serialize(writer, row[column]);
}
writer.WriteEndObject();
}
/// <summary>
/// Determines whether this instance can convert the specified value type.
/// </summary>
/// <param name="valueType">Type of the value.</param>
/// <returns>
/// <c>true</c> if this instance can convert the specified value type; otherwise, <c>false</c>.
/// </returns>
public override bool CanConvert(Type valueType)
{
return typeof(DataRow).IsAssignableFrom(valueType);
}
/// <summary>
/// Reads the JSON representation of the object.
/// </summary>
/// <param name="reader">The <see cref="JsonReader"/> to read from.</param>
/// <param name="objectType">Type of the object.</param>
/// <returns>The object value.</returns>
public override object ReadJson(JsonReader reader, Type objectType, JsonSerializer ser)
{
throw new NotImplementedException();
}
}
/// <summary>
/// Converts a DataTable to JSON. Note no support for deserialization
/// </summary>
public class DataTableConverter : JsonConverter
{
/// <summary>
/// Writes the JSON representation of the object.
/// </summary>
/// <param name="writer">The <see cref="JsonWriter"/> to write to.</param>
/// <param name="dataTable">The data table.</param>
/// <param name="ser">The JsonSerializer Object.</param>
public override void WriteJson(JsonWriter writer, object dataTable, JsonSerializer ser)
{
DataTable table = dataTable as DataTable;
DataRowConverter converter = new DataRowConverter();
writer.WriteStartObject();
writer.WritePropertyName("Rows");
writer.WriteStartArray();
foreach (DataRow row in table.Rows)
{
converter.WriteJson(writer, row, ser);
}
writer.WriteEndArray();
writer.WriteEndObject();
}
/// <summary>
/// Determines whether this instance can convert the specified value type.
/// </summary>
/// <param name="valueType">Type of the value.</param>
/// <returns>
/// <c>true</c> if this instance can convert the specified value type; otherwise, <c>false</c>.
/// </returns>
public override bool CanConvert(Type valueType)
{
return typeof(DataTable).IsAssignableFrom(valueType);
}
/// <summary>
/// Reads the JSON representation of the object.
/// </summary>
/// <param name="reader">The <see cref="JsonReader"/> to read from.</param>
/// <param name="objectType">Type of the object.</param>
/// <returns>The object value.</returns>
public override object ReadJson(JsonReader reader, Type objectType, JsonSerializer ser)
{
throw new NotImplementedException();
}
}
/// <summary>
/// Converts a <see cref="DataSet"/> object to JSON. No support for reading.
/// </summary>
public class DataSetConverter : JsonConverter
{
/// <summary>
/// Writes the JSON representation of the object.
/// </summary>
/// <param name="writer">The <see cref="JsonWriter"/> to write to.</param>
/// <param name="dataset">The dataset.</param>
/// <param name="ser">The JsonSerializer Object.</param>
public override void WriteJson(JsonWriter writer, object dataset, JsonSerializer ser)
{
DataSet dataSet = dataset as DataSet;
DataTableConverter converter = new DataTableConverter();
writer.WriteStartObject();
writer.WritePropertyName("Tables");
writer.WriteStartArray();
foreach (DataTable table in dataSet.Tables)
{
converter.WriteJson(writer, table, ser);
}
writer.WriteEndArray();
writer.WriteEndObject();
}
/// <summary>
/// Determines whether this instance can convert the specified value type.
/// </summary>
/// <param name="valueType">Type of the value.</param>
/// <returns>
/// <c>true</c> if this instance can convert the specified value type; otherwise, <c>false</c>.
/// </returns>
public override bool CanConvert(Type valueType)
{
return typeof(DataSet).IsAssignableFrom(valueType);
}
/// <summary>
/// Reads the JSON representation of the object.
/// </summary>
/// <param name="reader">The <see cref="JsonReader"/> to read from.</param>
/// <param name="objectType">Type of the object.</param>
/// <returns>The object value.</returns>
public override object ReadJson(JsonReader reader, Type objectType, JsonSerializer ser)
{
throw new NotImplementedException();
}
}
}
flexigrid是一个优秀的javascript表格控件，通过Json4FlexiGrid方法，我们可以很方便的为flexigrid提供数据源。
JsonConverter来源于Newtonsoft.Json，这是一个Json的开源项目，点击这里查看项目信息。