请查看下面用ASP.NET编写的代码。我的页面上有Google Places Search API。我有一个与Google API链接的txtSearch文本框控件。当您开始搜索时，它会显示Google商家信息提供的建议列表，您可以从中选择一个。我有一个FindCoordinates函数，它从txtSearch获取位置并将其传递给Google Maps API并获取坐标，然后用于填充listview控件。这里的问题是txtSearch不会触发AutoPostback或textChanged函数。我尝试了很多解决方案，onBlur，onKeyup，尝试从JavaScript调用静态函数，但似乎没有任何效果。
首页：
<%@ Page Title="Search Reviews" Language="C#" MasterPageFile="~/Site.master" AutoEventWireup="true" CodeFile="SearchReviews.aspx.cs" Inherits="Content_SearchReviews" %>
<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="cc1" %>
<%@ Register Assembly="System.Web.DataVisualization, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
Namespace="System.Web.UI.DataVisualization.Charting" TagPrefix="asp" %>
<asp:Content ID="Content1" ContentPlaceHolderID="MainContent" Runat="Server">
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<script type="text/javascript" src="https://maps.googleapis.com/maps/api/js?v=3.exp&libraries=places"></script>
<script type="text/javascript">
function LoadGoogleMAP() {
var markers = [];
var map = new google.maps.Map(document.getElementById('map_canvas'), {
mapTypeId: google.maps.MapTypeId.ROADMAP
});
var lat = document.getElementById('<%=txtLatitude.ClientID%>').value;
var lon = document.getElementById('<%=txtLongitude.ClientID%>').value;
var myLatlng = new google.maps.LatLng(lat, lon)
var defaultBounds = new google.maps.LatLngBounds(myLatlng, myLatlng);
//new google.maps.LatLng(-33.8902, 151.1759),
//new google.maps.LatLng(-33.8474, 151.2631));
map.fitBounds(defaultBounds);
// Create the search box and link it to the UI element.
var input = (document.getElementById('MainContent_txtSearch'));
map.controls[google.maps.ControlPosition.CENTER].push(input);
var searchBox = new google.maps.places.SearchBox((input));
// Listen for the event fired when the user selects an item from the
// pick list. Retrieve the matching places for that item.
google.maps.event.addListener(searchBox, 'places_changed', function () {
//PageMethods.UpdateResults("Hello");
var places = searchBox.getPlaces();
if (places.length == 0) {
return;
}
for (var i = 0, marker; marker = markers[i]; i++) {
marker.setMap(null);
}
// For each place, get the icon, place name, and location.
markers = [];
var bounds = new google.maps.LatLngBounds();
for (var i = 0, place; place = places[i]; i++) {
var image = {
url: place.icon,
size: new google.maps.Size(71, 71),
origin: new google.maps.Point(0, 0),
anchor: new google.maps.Point(17, 34),
scaledSize: new google.maps.Size(25, 25)
};
// Create a marker for each place.
var marker = new google.maps.Marker({
map: map,
icon: image,
title: place.name,
position: place.geometry.location
});
markers.push(marker);
bounds.extend(place.geometry.location);
}
map.fitBounds(bounds);
});
// current map's viewport.
google.maps.event.addListener(map, 'bounds_changed', function () {
var bounds = map.getBounds();
searchBox.setBounds(bounds);
});
}
//google.maps.event.addDomListener(window, 'load', LoadGoogleMAP);
</script>
<script type="text/javascript">
function RefreshUpdatePanel() {
__doPostBack('<%= txtSearch.ClientID %>', '');
};
</script>
<div class="row setPadding" style="background:#333333; color:#ffffff;">
<asp:Label ID="lblHeading" runat="server" Text="Search Reviews" Font-Bold="True" Font-Size="Large"></asp:Label><br />
</div>
<div class="row">
<div id="map_canvas"></div>
</div>
<div class="row setPadding">
<div class="col-lg-10 col-lg-offset-1 col-md-10 col-md-offset-1 col-sm-10 col-sm-offset-1 col-xs-12 col-xs-offset-1">
<div class="col-lg-12 col-md-12 col-sm-12 col-xs-12">
<asp:TextBox ID="txtSearch" CssClass="form-control" runat="server" placeholder="search address" AutoPostBack="true" OnTextChanged="txtSearch_TextChanged" EventName="TextChanged"></asp:TextBox>
</div>
<div class="hideContent">
<div class="col-lg-6 col-md-12 col-sm-12 col-xs-12">
<div class="form-group">
<asp:Label runat="server" AssociatedControlID="txtLatitude" CssClass="col-lg-6 col-md-3 col-sm-4 control-label">Latitude</asp:Label>
<div class="col-lg-6 col-md-5 col-sm-8">
<asp:TextBox runat="server" ID="txtLatitude" CssClass="form-control" Enabled="False" />
</div>
</div>
</div>
<div class="col-lg-6 col-md-12 col-sm-12 col-xs-12">
<div class="form-group">
<asp:Label runat="server" AssociatedControlID="txtLongitude" CssClass="col-lg-6 col-md-3 col-sm-4 control-label">Longitude</asp:Label>
<div class="col-lg-6 col-md-5 col-sm-8">
<asp:TextBox runat="server" ID="txtLongitude" CssClass="form-control" Enabled="False" />
</div>
</div>
</div>
</div>
<%--<div class="col-lg-12 col-md-12 col-sm-12 col-xs-12">--%>
<asp:ListView ID="lstSearchReviews" runat="server" DataSourceID="dsSearchReviews">
<ItemTemplate>
<div class="row ratingBackground">
<div class="col-lg-2 col-md-2 col-sm-2 col-xs-12">
<asp:Image ID="imgPhoto" ImageUrl='<%# GetImage(Eval("imgImage")) %>' CssClass="img-responsive center-block img-rounded" runat="server" />
</div>
<div class="col-lg-7 col-md-7 col-sm-7 col-xs-12">
<a href="ViewProperty.aspx?nPropertyId=<%# Eval("nPropertyId") %>"><asp:Label ID="Label1" runat="server" CssClass="ratingHeading" Text='<%# Eval("vcAddressLine1") %>' /> <asp:Label ID="Label2" runat="server" CssClass="ratingHeading" Text='<%# Eval("vcAddressLine2") %>' /></a>
<br>
<asp:Label ID="Label3" runat="server" Text='<%# Eval("vcCity") %>' /> <asp:Label ID="Label4" runat="server" CssClass="ratingHeading" Text='<%# Eval("vcPostCode") %>' />
<br />
<asp:Label ID="Label5" runat="server" Text='<%# Eval("vcCountry") %>' />
<br />
<asp:Label ID="Label6" runat="server" Text='<%# Eval("PropertyType") %>' />
</div>
<div class="col-lg-3 col-md-3 col-sm-3 col-xs-12">
<cc1:Rating ID="rating1" AutoPostBack="false"
StarCssClass="Star" WaitingStarCssClass="WaitingStar" EmptyStarCssClass="Star"
FilledStarCssClass="FilledStar" CurrentRating='<%# Eval("AverageRating") %>' runat="server" ReadOnly="true" ViewStateMode="Disabled">
</cc1:Rating>
<br />
<asp:Label ID="Label7" runat="server" CssClass="ratingHeading" Text='<%# Eval("TotalReviews") %>' /> <span class="ratingHeading"> Review(s)</span>
</div>
</div>
</ItemTemplate>
<LayoutTemplate>
<div class="col-lg-12 col-md-12 col-sm-12 col-xs-12">
<div id="itemPlaceholderContainer" runat="server" style="font-family: Verdana, Arial, Helvetica, sans-serif;">
<span runat="server" id="itemPlaceholder" />
</div>
</div>
<div class="col-lg-12 col-md-12 col-sm-12 col-xs-12">
<asp:DataPager ID="DataPager1" runat="server">
<Fields>
<asp:NextPreviousPagerField ButtonType="Button" ShowFirstPageButton="True" ShowLastPageButton="True" />
</Fields>
</asp:DataPager>
</div>
</LayoutTemplate>
<EmptyDataTemplate>
<div class="col-lg-12 col-md-12 col-sm-12 col-xs-12">
<p class="text-danger" style="margin:10px 0;"><span class="glyphicon glyphicon-exclamation-sign" aria-hidden="true""></span><strong> No results found. Please try a different search. </strong></p>
</div>
</EmptyDataTemplate>
</asp:ListView>
<asp:SqlDataSource ID="dsSearchReviews" runat="server" ConnectionString="<%$ ConnectionStrings:DefaultConnection %>" SelectCommand=""></asp:SqlDataSource>
</div>
</div>
</ContentTemplate>
</asp:UpdatePanel>
</asp:Content>
代码背后：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.IO;
using System.Net;
using System.Text;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
using System.Drawing;
public partial class Content_SearchReviews : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
Session["CurrentPage"] = "SearchReviews.aspx";
if (!IsPostBack)
{
if (Session["FormattedAddress"] != null)
{
txtSearch.Text = Convert.ToString(Session["FormattedAddress"]);
}
}
FindCoordinates(null, null);
setDataSource();
}
protected void FindCoordinates(object sender, EventArgs e)
{
string sLocation = "";
if (txtSearch.Text == "")
{
sLocation = "London, United Kingdom";
}
else
{
sLocation = txtSearch.Text;
}
string url = "http://maps.google.com/maps/api/geocode/xml?address=" + sLocation + "&partial_match=false&location_type=ROOFTOP&street_address=" + sLocation + "&sensor=false";
WebRequest request = WebRequest.Create(url);
using (WebResponse response = (HttpWebResponse)request.GetResponse())
{
using (StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.UTF8))
{
DataSet dsResult = new DataSet();
dsResult.ReadXml(reader);
DataTable dtCoordinates = new DataTable();
dtCoordinates.Columns.AddRange(new DataColumn[4] { new DataColumn("Id", typeof(int)),
new DataColumn("Address", typeof(string)),
new DataColumn("Latitude",typeof(string)),
new DataColumn("Longitude",typeof(string)) });
foreach (DataRow row in dsResult.Tables["result"].Rows)
{
string geometry_id = dsResult.Tables["geometry"].Select("result_id = " + row["result_id"].ToString())[0]["geometry_id"].ToString();
DataRow location = dsResult.Tables["location"].Select("geometry_id = " + geometry_id)[0];
dtCoordinates.Rows.Add(row["result_id"], row["formatted_address"], location["lat"], location["lng"]);
txtLatitude.Text = Convert.ToString(location["lat"]);
txtLongitude.Text = Convert.ToString(location["lng"]);
ScriptManager.RegisterStartupScript(this, GetType(), "LoadGoogleMAP", "LoadGoogleMAP();", true);
}
}
}
}
protected void setDataSource()
{
dsSearchReviews.SelectCommand = "Select a.nPropertyId, a.vcCompleteAddress, a.vcAddressLine1, a.vcAddressLine2, a.vcCity, a.vcPostCode, a.vcCountry, CASE nPropertyTypeId WHEN 1 Then 'Flat' WHEN 2 THEN 'House' When 3 THEN 'House (Semi-Detatched)' WHEN 4 THEN 'HOUSE (Detatched)' END Propertytype, (Select cast(avg(flRatingOverall) as int) flRatingOverall From dbo.Reviews Where nPropertyId = a.nPropertyId) AverageRating, (Select COUNT(nReviewId) TotalRatings From dbo.Reviews Where nPropertyId = a.nPropertyId) TotalReviews, SQRT(POWER(dLatitude - " + Convert.ToDouble(txtLatitude.Text) + ", 2) + POWER(dLongitude - " + Convert.ToDouble(txtLongitude.Text) + ", 2)) * 62.1371192 AS DistanceFromAddress, imgImage From Properties a WHERE ABS(dLatitude - " + Convert.ToDouble(txtLatitude.Text) + ") < 0.50 AND ABS(dLongitude - " + Convert.ToDouble(txtLongitude.Text) + ") < 0.50";
dsSearchReviews.DataBind();
lstSearchReviews.DataBind();
}
public string GetImage(object img)
{
return "data:image/png;base64," + Convert.ToBase64String((byte[])img);
}
protected void txtSearch_TextChanged(object sender, EventArgs e)
{
FindCoordinates(null, null);
setDataSource();
}
//[System.Web.Services.WebMethod]
//public static string UpdateResults(string greeting)
//{
// Content_SearchReviews updatePage = new Content_SearchReviews();
// updatePage.Session["FormattedAddress"] = updatePage.txtSearch.Text;
// updatePage.FindCoordinates(null, null);
// updatePage.setDataSource();
// return greeting;
//}
}
答案 0 :(得分：0)
经过大量调试后，我发现setDataSource（）函数阻止了自动后备。我设置了listview的属性EnableViewState =“false”，这就是诀窍。现在工作正常。