AJAX is implemented in TextBox, dynamically displayed in the database into the drop-down box.

xiaoxiao2021-04-04  259

1. Create an ASPX page, HTML code

Webform1 </ title> <script language = "javascript"> // City ------------------------- ----- function cityResult () {var city = document.getElementById ( "TextBox1"); WebForm1.GetCityList (city.value, get_city_Result_CallBack);} function get_city_Result_CallBack (response) {if (! response.value = null) { // debugger;. document.getElementById ( "DropDownList1") style.display = "block"; document.getElementById ( "DropDownList1") length = 0;. var ds = response.value;! if (ds = null && typeof ( DS) == "Object" && Ds.tables! = null) {for (var i = 0; i <ds.tables [0] .Rows.Length; i ) {var name = ds.tables [0] .row s [i] .city; var ID = ds.tables [0] .rows [i] .cityId; document.getlementByid ("DropDownList1"). Options.add (new option (name, id));}}} else {Document.getlementByid ("DropDownList1"). Style.display = "none";} return} function getdata () {var province = document.getlementByid ("DropDownList1");</p> <p>var pindex = province.selectedIndex; var pValue = province.options [pindex] .value; var pText = province.options [pindex] .text;. document.getElementById ( "<% = TextBox1.ClientID%>") innerText = pText } </ Script> </ head> <body> <form id = "form1" method = "post" runat = "server"> <ask: textbox id = "textbox1" runat = "server"> </ asp: TextBox> <ASP: DropDownList ID = "DropdownList1" runat = "server" width = "192px" style = "Display: None"> </ asp: dropdownloadList> </ form> </ body> </ html> 2.cs codes using System; using System.Collections; using System.ComponentModel; using System.Data; using System.Drawing; using System.Web; using System.Web.SessionState; using System.Web.UI; using System.Web .UI.WebControls; using System.Web.UI.HtmlControls; using System.Data.SqlClient; namespace ajaxselect {/ ** <summary> /// Summary description for WebForm1 /// </ summary> public class WebForm1: System. .Web.ui.page {protected SY stem.Web.UI.WebControls.TextBox TextBox1; protected System.Web.UI.WebControls.DropDownList DropDownList1; private void Page_Load (object sender, System.EventArgs e) {Ajax.Utility.RegisterTypeForAjax (typeof (WebForm1)); if ( "Page.ispostback) {this.textbox1.attributes.add (" onchange "," "" ""); this.dropdownlist1.attributes.add ("onclick", "getData ();");}}</p> <p>Web Form Designer generated code # region Web Form Designer generated code override protected void OnInit (EventArgs e) {// // CODEGEN: This call is required by the ASP.NET Web Form Designer // InitializeComponent (); base.OnInit (. e);} / ** <summary> /// Required Method for Designer Support - Do Not Modify //////// </ summary> private void initializecomponent () {this. Load = new system.eventhandler (this.page_load);} #ENDREGION</p> <p>GetCityList # region GetCityList [Ajax.AjaxMethod (Ajax.HttpSessionStateRequirement.Read)] public DataSet GetCityList (int provinceid) {string sql = "select * from where father like '% provinceid "% city "'"; return GetDataSet (sql );} #endregion GetDataSet # region GetDataSet public static DataSet GetDataSet (string sql) {string ConnectionString = System.Configuration.ConfigurationSettings.AppSettings [ "ConnectionString"]; SqlDataAdapter sda = new SqlDataAdapter (sql, ConnectionString); DataSet ds = new DataSet (); SDA.FILL (DS); Return DS;} #ENDREGION</p> <p>}</p></div><div class="text-center mt-3 text-grey"> 转载请注明原文地址:https://www.9cbs.com/read-131772.html</div><div class="plugin d-flex justify-content-center mt-3"></div><hr><div class="row"><div class="col-lg-12 text-muted mt-2"><i class="icon-tags mr-2"></i><span class="badge border border-secondary mr-2"><h2 class="h6 mb-0 small"><a class="text-secondary" href="tag-2.html">9cbs</a></h2></span></div></div></div></div><div class="card card-postlist border-white shadow"><div class="card-body"><div class="card-title"><div class="d-flex justify-content-between"><div><b>New Post</b>(<span class="posts">0</span>) </div><div></div></div></div><ul class="postlist list-unstyled"> </ul></div></div><div class="d-none threadlist"><input type="checkbox" name="modtid" value="131772" checked /></div></div></div></div></div><footer class="text-muted small bg-dark py-4 mt-3" id="footer"><div class="container"><div class="row"><div class="col">CopyRight © 2020 All Rights Reserved </div><div class="col text-right">Processed: <b>0.038</b>, SQL: <b>9</b></div></div></div></footer><script src="./lang/en-us/lang.js?2.2.0"></script><script src="view/js/jquery.min.js?2.2.0"></script><script src="view/js/popper.min.js?2.2.0"></script><script src="view/js/bootstrap.min.js?2.2.0"></script><script src="view/js/xiuno.js?2.2.0"></script><script src="view/js/bootstrap-plugin.js?2.2.0"></script><script src="view/js/async.min.js?2.2.0"></script><script src="view/js/form.js?2.2.0"></script><script> var debug = DEBUG = 0; var url_rewrite_on = 1; var url_path = './'; var forumarr = {"1":"Tech"}; var fid = 1; var uid = 0; var gid = 0; xn.options.water_image_url = 'view/img/water-small.png'; </script><script src="view/js/wellcms.js?2.2.0"></script><a class="scroll-to-top rounded" href="javascript:void(0);"><i class="icon-angle-up"></i></a><a class="scroll-to-bottom rounded" href="javascript:void(0);" style="display: inline;"><i class="icon-angle-down"></i></a></body></html><script> var forum_url = 'list-1.html'; var safe_token = 'TbOhCyj3muJ9yVg7rFeWToFIG2Gerk7aIB6nPnREv2c1vvp3Z50m0y8tWAWS464j2RadfTHsLfKKn7oqrpINHw_3D_3D'; var body = $('body'); body.on('submit', '#form', function() { var jthis = $(this); var jsubmit = jthis.find('#submit'); jthis.reset(); jsubmit.button('loading'); var postdata = jthis.serializeObject(); $.xpost(jthis.attr('action'), postdata, function(code, message) { if(code == 0) { location.reload(); } else { $.alert(message); jsubmit.button('reset'); } }); return false; }); function resize_image() { var jmessagelist = $('div.message'); var first_width = jmessagelist.width(); jmessagelist.each(function() { var jdiv = $(this); var maxwidth = jdiv.attr('isfirst') ? first_width : jdiv.width(); var jmessage_width = Math.min(jdiv.width(), maxwidth); jdiv.find('img, embed, iframe, video').each(function() { var jimg = $(this); var img_width = this.org_width; var img_height = this.org_height; if(!img_width) { var img_width = jimg.attr('width'); var img_height = jimg.attr('height'); this.org_width = img_width; this.org_height = img_height; } if(img_width > jmessage_width) { if(this.tagName == 'IMG') { jimg.width(jmessage_width); jimg.css('height', 'auto'); jimg.css('cursor', 'pointer'); jimg.on('click', function() { }); } else { jimg.width(jmessage_width); var height = (img_height / img_width) * jimg.width(); jimg.height(height); } } }); }); } function resize_table() { $('div.message').each(function() { var jdiv = $(this); jdiv.find('table').addClass('table').wrap('<div class="table-responsive"></div>'); }); } $(function() { resize_image(); resize_table(); $(window).on('resize', resize_image); }); var jmessage = $('#message'); jmessage.on('focus', function() {if(jmessage.t) { clearTimeout(jmessage.t); jmessage.t = null; } jmessage.css('height', '6rem'); }); jmessage.on('blur', function() {jmessage.t = setTimeout(function() { jmessage.css('height', '2.5rem');}, 1000); }); $('#nav li[data-active="fid-1"]').addClass('active'); </script>