datatable生成easyui的json格式汇总( 转)

转自 http://www.cnblogs.com/WikStone/archive/2012/07/02/2573137.html

目前项目没有使用第三方的json转换库，都是根据json格式进行字符串拼接。

生成Combobox json格式：

 /// <summary>
        /// 生成Combobox JSON格式
        /// </summary>
        /// <param name="dt">数据源DataTable</param>
        /// <returns>Combobox的json格式  [{ "id":1,"text":"text1"}] </returns>
        public static string CreateJsonDictClass(DataTable dt)
        {
            StringBuilder JsonString = new StringBuilder();
            //Exception Handling        

            if (dt != null)
            {
                JsonString.Append("[");                
                    for (int i = 0; i < dt.Rows.Count; i++)
                    {
                        if(i<dt.Rows.Count-1)
                        {



                        JsonString.Append("{ ");
                        JsonString.Append("\"id\": ");
                        JsonString.Append(dt.Rows[i]["ID"] +",");
                        JsonString.Append("\"text\": ");
                        JsonString.Append("\"" + dt.Rows[i]["Title"]+"\"");
                        JsonString.Append("},");
                         }
                        if (i == dt.Rows.Count - 1)
                        {
                            JsonString.Append("{ ");
                            JsonString.Append("\"id\": ");
                            JsonString.Append(dt.Rows[i]["ID"] + ",");
                            JsonString.Append("\"text\": ");
                            JsonString.Append("\"" + dt.Rows[i]["Title"] + "\"");
                            JsonString.Append("}");
 
                        }
                    }
                    JsonString.Append("]");
                    return JsonString.ToString();
            }
          
            else
                return null;
        }

生成DataGrid json格式:

 /// <summary>
        /// 将DataTable中的数据转换成JSON格式
        /// </summary>
        /// <param name="dt">数据源DataTable</param>
        /// <param name="displayCount">是否输出数据总条数</param>
        /// <param name="totalcount">JSON中显示的数据总条数</param>
        /// <returns></returns>
        public static string CreateJsonParameters(DataTable dt, bool displayCount, int totalcount)
        {
            StringBuilder JsonString = new StringBuilder();
            //Exception Handling        

            if (dt != null)
            {
                JsonString.Append("{ ");
                JsonString.Append("\"rows\":[ ");
                for (int i = 0; i < dt.Rows.Count; i++)
                {
                    JsonString.Append("{ ");
                    for (int j = 0; j < dt.Columns.Count; j++)
                    {
                        if (j < dt.Columns.Count - 1)
                        {
                            //if (dt.Rows[i][j] == DBNull.Value) continue;
                            if (dt.Columns[j].DataType == typeof(bool))
                            {
                                JsonString.Append("\"JSON_" + dt.Columns[j].ColumnName.ToLower() + "\":" +
                                                  dt.Rows[i][j].ToString().ToLower() + ",");
                            }
                            else if (dt.Columns[j].DataType == typeof(string))
                            {
                                JsonString.Append("\"JSON_" + dt.Columns[j].ColumnName.ToLower() + "\":" + "\"" +
                                                  dt.Rows[i][j].ToString().Replace("\"", "\\\"") + "\",");
                            }
                            else
                            {
                                JsonString.Append("\"JSON_" + dt.Columns[j].ColumnName.ToLower() + "\":" + "\"" + dt.Rows[i][j] + "\",");
                            }
                        }
                        else if (j == dt.Columns.Count - 1)
                        {
                            //if (dt.Rows[i][j] == DBNull.Value) continue;
                            if (dt.Columns[j].DataType == typeof(bool))
                            {
                                JsonString.Append("\"JSON_" + dt.Columns[j].ColumnName.ToLower() + "\":" +
                                                  dt.Rows[i][j].ToString().ToLower());
                            }
                            else if (dt.Columns[j].DataType == typeof(string))
                            {
                                JsonString.Append("\"JSON_" + dt.Columns[j].ColumnName.ToLower() + "\":" + "\"" +
                                                  dt.Rows[i][j].ToString().Replace("\"", "\\\"") + "\"");
                            }
                            else
                            {
                                JsonString.Append("\"JSON_" + dt.Columns[j].ColumnName.ToLower() + "\":" + "\"" + dt.Rows[i][j] + "\"");
                            }
                        }
                    }
                    /*end Of String*/
                    if (i == dt.Rows.Count - 1)
                    {
                        JsonString.Append("} ");
                    }
                    else
                    {
                        JsonString.Append("}, ");
                    }
                }
                JsonString.Append("]");

                if (displayCount)
                {
                    JsonString.Append(",");

                    JsonString.Append("\"total\":");
                    JsonString.Append(totalcount);
                }

                JsonString.Append("}");
                return JsonString.ToString().Replace("\n", "");
            }
            else
            {
                return null;
            }
        }

生成Tree      json格式：

/// <summary>    /// 根据DataTable生成Json树结构    /// </summary>    /// <param name="tabel">数据源</param>    /// <param name="idCol">ID列</param>    /// <param name="txtCol">Text列</param>    /// <param name="rela">关系字段</param>    /// <param name="pId">父ID</param>    StringBuilder result = new StringBuilder();    StringBuilder sb = new StringBuilder();    private void GetTreeJsonByTable(DataTable tabel, string idCol, string txtCol, string rela, object pId)    {        result.Append(sb.ToString());        sb.Clear();        if (tabel.Rows.Count > 0)        {            sb.Append("[");            string filer = string.Format("{0}='{1}'", rela, pId);            DataRow[] rows = tabel.Select(filer);            if (rows.Length > 0)            {                foreach (DataRow row in rows)                {                    sb.Append("{\"id\":\"" + row[idCol] + "\",\"text\":\"" + row[txtCol] + "\",\"state\":\"open\"");                    if (tabel.Select(string.Format("{0}='{1}'", rela, row[idCol])).Length > 0)                    {                        sb.Append(",\"children\":");                        GetTreeJsonByTable(tabel, idCol, txtCol, rela, row[idCol]);                        result.Append(sb.ToString());                        sb.Clear();                    }                    result.Append(sb.ToString());                    sb.Clear();                    sb.Append("},");                }                sb = sb.Remove(sb.Length - 1, 1);            }            sb.Append("]");            result.Append(sb.ToString());            sb.Clear();        }    }

调用方法很简单，运行这个void 类型的函数，然后取result 的值就行了，

GetTreeJsonByTable(datatable, "id", "title", "pid", "0");string content = result.ToString();