[ASP.net教程]生成json格式

html頁(yè)面

 <input type="button" value="重新生成JSON" class="button1" id="createjson" />

 javascript部分

 <script type="text/javascript"> $(function () {       //生成JSON      $("#createjson").click(function () {        $.post("NewsCategory.aspx?action=create", function (json) {          alert(json.msg);         });      });   });</script>

后臺(tái)代碼

　　protected void Page_Load(object sender, EventArgs e)  {    if (Request.Headers["X-Requested-With"] != null && Request.Headers["X-Requested-With"].ToLower() == "".ToLower())    {      Response.Clear();      Response.ContentType = "application/json";      if (Request["action"] == "create")      {        Response.Write(CreateJson());      }      Response.End();    }  }

 　　/// <summary>  /// 生成商家類別Json  /// </summary>  /// <returns></returns>  protected string CreateJson()  {        System.Web.Script.Serialization.JavaScriptSerializer json = new System.Web.Script.Serialization.JavaScriptSerializer();　　　　　//初始化（引用空間using System.Text;）
    StringBuilder sb = new StringBuilder();    var list = Express.BLL.NewsCategory.Get();    foreach (var item in list)    {      if (sb.Length > 0)        sb.Append(",");      sb.Append(string.Format("{{\"id\":{0},\"name\":\"{1}\",\"pid\":{2},\"itemvalue\":\"{3}\"", item.Id, GetUnicode(item.ItemName), item.ParentId, item.ItemValue));      sb.Append("}");    }　　　　　//返回與Web服務(wù)器上的指定虛擬路徑相對(duì)應(yīng)的物理文件路徑
    string filePath = Server.MapPath(@"/common/newscategoryJson.js"); 　　　　//創(chuàng)建一個(gè)新文件，并寫入指定字符串，若目標(biāo)文件已存在，則覆蓋該文件
    System.IO.File.WriteAllText(filePath, "[" + sb.ToString() + "]", System.Text.Encoding.UTF8);        return json.Serialize(new { code = 1, msg = "生成完成" });  }

 漢字轉(zhuǎn)為Unicode編碼

 /// <summary>  /// 得到漢字的Unicode編碼  /// </summary>  protected string GetUnicode(string text)  {    string result = "";    for (int i = 0; i < text.Length; i++)    {      if ((int)text[i] > 32 && (int)text[i] < 127)      {        result += text[i].ToString();      }      else        result += string.Format("\\u{0:x4}", (int)text[i]);    }    return result;  }

數(shù)據(jù)庫(kù)部分

    /// 獲取全部    /// </summary>    public List<Model.NewsCategory> Get()    {      string sql = "select * from NewsCategory order by case when ParentId=0 then Id*10000 else ParentId*10000+Id end";      List<Model.NewsCategory> list = new List<Model.NewsCategory>();      using (SqlDataReader dr = DBUtility.SqlHelper.ExecuteReader(ConnString.connReadonly, CommandType.Text, sql, null))      {        while (dr.Read())        {          Model.NewsCategory model = new Model.NewsCategory();          object obj;          obj = dr["Id"];          if (obj != null && obj != DBNull.Value)          {            model.Id = (int)obj;          }          obj = dr["SortValue"];          if (obj != null && obj != DBNull.Value)          {            model.SortValue = (int)obj;          }          obj = dr["ParentId"];          if (obj != null && obj != DBNull.Value)          {            model.ParentId = (int)obj;          }          model.ItemName = dr["ItemName"].ToString();          model.ItemValue=dr["ItemValue"].ToString();          list.Add(model);        }      }      return list;    }

運(yùn)行結(jié)果
common/newscategoryJson.js

[{"id":31,"name":"\u65b0\u95fb\u4e2d\u5fc3","pid":0,"itemvalue":"|0|"},
{"id":51,"name":"\u4f01\u4e1a\u5feb\u8baf","pid":31,"itemvalue":"|0|31|"},
{"id":52,"name":"\u4f01\u4e1a\u516c\u544a","pid":31,"itemvalue":"|0|31|"},
{"id":53,"name":"\u884c\u4e1a\u52a8\u6001","pid":31,"itemvalue":"|0|31|"},
{"id":91,"name":"\u65b0\u95fb\u4e2d\u5fc3","pid":31,"itemvalue":"|0|31|"},
{"id":93,"name":"\u4f01\u4e1a\u5feb\u8baf","pid":31,"itemvalue":"|0|31|"},
{"id":94,"name":"\u4f01\u4e1a\u516c\u544a","pid":31,"itemvalue":"|0|31|"},
{"id":180,"name":"\u6d4b\u8bd5","pid":31,"itemvalue":"|0|31|"},
{"id":181,"name":"\u6d4b\u8bd5111","pid":31,"itemvalue":"|0|31|"},


{"id":54,"name":"\u5173\u4e8e\u76df\u53cb\u634c\u634c","pid":0,"itemvalue":"|0|"},
{"id":55,"name":"\u4f01\u4e1a\u6982\u51b5","pid":54,"itemvalue":"|0|54|"},
{"id":56,"name":"\u4f01\u4e1a\u6587\u5316","pid":54,"itemvalue":"|0|54|"},
{"id":57,"name":"\u4f01\u4e1a\u53d1\u5c55","pid":54,"itemvalue":"|0|54|"}
......
]

 涉及的知識(shí)點(diǎn)

1、Server.MapPath(string path);

2、System.IO.File.WriteAllText(sting path,string contents,Encoding encoding);