


How to use Ajax to implement non-refresh linkage of drop-down boxes in jQuery
This article mainly introduces in detail the implementation of non-refresh linkage of drop-down boxes based on jQuery Ajax. It has a certain reference value. Interested friends can refer to it.
The examples in this article share jQuery with everyone. The specific code for Ajax to implement non-refresh linkage of the drop-down box is for your reference. The specific content is as follows
HTML code:
@{ Layout = null; } @using DAL; @using System.Data; @{ AreaDal areaDal = new AreaDal(); string areaId = ViewBag.areaId; DataRow drArea = areaDal.GetArea(areaId); string countyId = drArea == null ? "-1" : drArea["countyId"].ToString(); DataRow drCounty = areaDal.GetCounty(countyId); string cityId = drCounty == null ? "-1" : drCounty["cityId"].ToString(); DataRow drCity = areaDal.GetCity(cityId); string provinceId = drCity == null ? "-1" : drCity["provinceId"].ToString(); } <!DOCTYPE html> <html> <head> <title>商圈选择</title> <script type="text/javascript"> //选中 function select(selId, id, callback) { $("#" + selId).val(id); if (callback) callback(); } //获取省列表 function getProvinces(callback) { $.ajax({ type: "POST", url: "@Url.Content("~/Backstage/Area/GetProvinces")", data: {}, success: function (text) { $("#province").html(text); if (callback) callback(); }, error: function () { } }); } //获取市列表 function getCities(pid, callback) { $.ajax({ type: "POST", url: "@Url.Content("~/Backstage/Area/GetCities")", data: { "provinceId": pid, }, success: function (text) { $("#city").html(text); if (callback) callback(); }, error: function () { } }); } //获取区县列表 function getCounties(pid, callback) { $.ajax({ type: "POST", url: "@Url.Content("~/Backstage/Area/GetCounties")", data: { "cityId": pid, }, success: function (text) { $("#county").html(text); if (callback) callback(); }, error: function () { } }); } //获取商圈列表 function getAreas(pid, callback) { $.ajax({ type: "POST", url: "@Url.Content("~/Backstage/Area/GetAreas")", data: { "countyId": pid, }, success: function (text) { $("#area").html(text); if (callback) callback(); }, error: function () { } }); } </script> </head> <body> <select id="province"> <option value="-1">==请选择==</option> </select> <select id="city"> <option value="-1">==请选择==</option> </select> <select id="county"> <option value="-1">==请选择==</option> </select> <select id="area"> <option value="-1">==请选择==</option> </select> <script type="text/javascript"> //选择省 $("#province").change(function () { var id = $(this).find("option:selected").val(); getCities(id, function () { $("#city").change(); }); }); //选择市 $("#city").change(function () { var id = $(this).find("option:selected").val(); getCounties(id, function () { $("#county").change(); }); }); //选择区县 $("#county").change(function () { var id = $(this).find("option:selected").val(); getAreas(id, function () { $("#area").change(); }); }); getProvinces(function () { select("province", '@provinceId', function () { getCities('@provinceId', function () { select("city", '@cityId', function () { getCounties('@cityId', function () { select("county", '@countyId', function () { getAreas('@countyId', function () { select("area", '@areaId'); }); }); }); }); }); }); }); </script> </body> </html>
Controller code:
using System; using System.Collections.Generic; using System.Data; using System.Linq; using System.Text; using System.Web.Mvc; using DAL; namespace Controllers.Backstage { /// <summary> /// 行政区划 /// </summary> public class AreaController : AdminBaseController { #region 构造函数及变量 private SQLiteHelper.SQLiteHelper sqliteHelper; private AreaDal areaDal; public AreaController() { sqliteHelper = new SQLiteHelper.SQLiteHelper(); areaDal = new AreaDal(); } #endregion #region 行政区划商圈级联选择页面 public ActionResult AreaSelect() { return PartialView(); } #endregion #region 获取全部省 public ActionResult GetProvinces() { DataTable dt = areaDal.GetProvincesAll(); StringBuilder sbHtml = new StringBuilder(); sbHtml.Append("<option value='-1'>==请选择==</option>"); foreach (DataRow dr in dt.Rows) { sbHtml.AppendFormat("<option value='{0}'>{1}</option>", dr["id"].ToString(), dr["name"].ToString()); } return Content(sbHtml.ToString()); } #endregion #region 根据省获取市 public ActionResult GetCities(string provinceId) { DataTable dt = areaDal.GetCities(provinceId); StringBuilder sbHtml = new StringBuilder(); sbHtml.Append("<option value='-1'>==请选择==</option>"); foreach (DataRow dr in dt.Rows) { sbHtml.AppendFormat("<option value='{0}'>{1}</option>", dr["id"].ToString(), dr["name"].ToString()); } return Content(sbHtml.ToString()); } #endregion #region 根据市获取区县 public ActionResult GetCounties(string cityId) { DataTable dt = areaDal.GetCounties(cityId); StringBuilder sbHtml = new StringBuilder(); sbHtml.Append("<option value='-1'>==请选择==</option>"); foreach (DataRow dr in dt.Rows) { sbHtml.AppendFormat("<option value='{0}'>{1}</option>", dr["id"].ToString(), dr["name"].ToString()); } return Content(sbHtml.ToString()); } #endregion #region 根据区县获取商圈 public ActionResult GetAreas(string countyId) { DataTable dt = areaDal.GetAreas(countyId); StringBuilder sbHtml = new StringBuilder(); sbHtml.Append("<option value='-1'>==请选择==</option>"); foreach (DataRow dr in dt.Rows) { sbHtml.AppendFormat("<option value='{0}'>{1}</option>", dr["id"].ToString(), dr["name"].ToString()); } return Content(sbHtml.ToString()); } #endregion } }
The above is what I compiled for everyone Yes, I hope it will be helpful to everyone in the future.
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