【发布时间】：2014-09-11 14:40:41
【问题描述】：
我已经坚持了 2 天了。我最初使用 HTMLSelect 元素并取得了成功，直到我意识到我不知道如何从后面的代码中为它们赋值。这是使用 HTMLSelect 元素时的代码，它使页面元素的行为符合我的要求：
<select id="cboCountry" class="autoTBComplete"/>
<select id="cboState" class="autoTBComplete" />
<script type="text/javascript">
$(document).ready(function () {
$("#cboCountry").bind("change", ValidateCountryInput);
$("#cboState").bind("change", ValidateStateInput);
$.ajax({
type: "POST",
url: "AjaxService.asmx/GetCountryList",
contentType: "application/json; charset=utf-8",
data: "{}",
datatype:"json",
success: function (data) {
var d = data.d
$(d).each(function (i) {
$('#cboCountry').append("<option value=" + d[i] + ">" + d[i] + "</option>");
});
},
error: function (XMLHttpRequest, textStatus, errorThrown) {
alert(textStatus);
}
});
});
function ValidateCountryInput() {
if (CheckUSAorCAN()) {
$.ajax({
type: "POST",
url: "AjaxService.asmx/GetStateList",
contentType: "application/json; charset=utf-8",
data: "{}",
datatype: "json",
success: function (data) {
var d = data.d
$(d).each(function (i) {
$('#cboState').append("<option value=" + d[i] + ">" + d[i] + "</option>");
});
},
error: function (XMLHttpRequest, textStatus, errorThrown) {
alert(textStatus);
}
});
$("[id$='cboState']").attr('style', "background:#ffd1d1; box-shadow: 0 0 20px #ff7a7a; width:64%;");
}
else {
$("[id$='cboState']").val("");
$("[id$='cboState']").attr('style', "width:5%");
$("[id$='cboState']").classname ="autotbComplete";
};
};
function ValidateStateInput() {
var txt = $('#cboState').val();
if (CheckUSAorCAN()) {
if (txt.length > 0) {
$("[id$='cboState']").attr('style', "width:64%");
$("[id$='cboState']").classname = "autotbComplete";
}
else {
$("[id$='cboState']").attr('style', "background:#ffd1d1; box-shadow: 0 0 20px #ff7a7a; width:64%;");
}
}
else {
$("[id$='cboState']").attr('style', "background:#ffd1d1; box-shadow: 0 0 20px #ff7a7a; width:64%;");
};
}
function CheckUSAorCAN() {
var txt = $('#cboCountry').val();
txt = toAllCaps(txt);
txt = txt.replace("([^A-Z])+");
return "US" == txt || "USA" == txt || "UNITEDSTATES" == txt || "CANADA" == txt;
}
function toAllCaps(string) { //jQuery toUpperCase() doesn't work on strings for IE 6-10
if (string != null) {
var input = string.split("")
for (i = 0; i < input.length; i++) {
input[i] = string.charAt(i).toUpperCase()
};
return input.join("")
}
return string
};
完成该工作后，我意识到我在后面的代码中存在问题，特别是在以下函数中，我正在为元素分配值或从元素中检索值。我可以使用 Response.Params 从框中获取值，但不知道如何分配值或如何从后面的代码中隐藏/禁用该字段，因为我不能执行 cboCountry.enabled = false on从后面的代码中选择元素。如果元素是 ASP.NET DropDownList，则代码有效（注意：我从该属性中删除了不相关的字段。cbo 前缀是应用程序只是使用组合框的 WinApp 时的剩余部分）。
Private Property InputFieldsControl As CustomerDataFields
Get
Dim cdf As New CustomerDataFields
cdf.Country = cboCountry.Text
cdf.State = cboState.Text
Return cdf
End Get
Set(ByVal cdf As CustomerDataFields)
If Not cboCountry.Items.Contains(New ListItem(cdf.Country)) Then
cboCountry.Items.Add(cdf.Country)
End If
cboCountry.Text = cdf.Country
If Not cboState.Items.Contains(New ListItem(cdf.State)) Then
cboState.Items.Add(cdf.State)
End If
cboState.Text = cdf.State
End Set
End Property
因为意识到 HTMLSelect 元素无法与我的代码一起使用。我试图使相同的网页和 javascript 与 DropDownLists 一起使用，但没有成功。从上面更改的代码如下。注意 cmets，因为这些是新问题。特别是未触发的事件和 CheckUSAorCAN() 不断从 cboCountry 检索所选值的空值。
<asp:DropDownList Width="66%" CssClass="tbSkin" ID="cboCountry" runat="server" ></asp:DropDownList>
<asp:DropDownList Width="66%" CssClass="tbSkin" ID="cboState" runat="server" ></asp:DropDownList>
<script type="text/javascript">
$(document).ready(function () {
$.ajax({
type: "POST",
url: "AjaxService.asmx/GetCountryList",
contentType: "application/json; charset=utf-8",
data: "{}",
datatype:"json",
success: function (data) {
var d = data.d;
$(d).each(function (i) {
var ddlref = document.getElementById("cphContents_InputParams_cboCountry");
addItem(ddlref,d[i]);
});
},
error: function (XMLHttpRequest, textStatus, errorThrown) {
alert(textStatus);
}
});
$("#cboCountry").bind("change", onCountryChange); //does not bind or fire the event
$("#cboState").bind("change", onStateChange); //does not bind or fire the event
});
function onCountryChange(e) {
if (CheckUSAorCAN()) {
$.ajax({
type: "POST",
url: "AjaxService.asmx/GetStateList",
contentType: "application/json; charset=utf-8",
data: "{}",
datatype: "json",
success: function (data) {
var d = data.d;
$(d).each(function (i) {
var ddlref = document.getElementById("cphContents_InputParams_cboState");
addItem(ddlref, d[i]);
});
},
error: function (XMLHttpRequest, textStatus, errorThrown) {
alert(textStatus);
}
});
$("[id$='cboState']").attr('style', "background:#ffd1d1; box-shadow: 0 0 20px #ff7a7a; width:64%;");
}
else {
$("[id$='cboState']").val("");
$("[id$='cboState']").attr('style', "width:5%");
$("[id$='cboState']").classname = "autotbComplete";
};
};
function onStateChange(e) {
var txt = $('#cboState').val();
if (CheckUSAorCAN()) {
if (txt.length > 0) {
$("[id$='cboState']").attr('style', "width:64%");
$("[id$='cboState']").classname = "autotbComplete";
}
else {
$("[id$='cboState']").attr('style', "background:#ffd1d1; box-shadow: 0 0 20px #ff7a7a; width:64%;");
};
}
else {
$("[id$='cboState']").attr('style', "background:#ffd1d1; box-shadow: 0 0 20px #ff7a7a; width:64%;");
};
};
function CheckUSAorCAN() {
var txt = $('#cboCountry').val();
var e = document.getElementById("cphContents_InputParams_cboState");
var index = e.selectedIndex; //does not work
var strUser = e.options[e.selectedIndex]; //does not work
if (txt != null) { //always comes up null
txt = toAllCaps(txt);
txt = txt.replace("([^A-Z])+");
return "US" == txt || "USA" == txt || "UNITEDSTATES" == txt || "CANADA" == txt;
}
return false;
};
function addItem(ddlref, item) {
var option1 = document.createElement("option");
option1.text = item;
option1.value = item;
ddlref.options.add(option1);
};
因为通过 jQuery 绑定后更改事件没有触发，所以我将它们绑定在标记代码中，如下所示：
<asp:DropDownList Width="66%" CssClass="autoTBComplete" ID="cboCountry" runat="server" onchange="onCountryChange()"></asp:DropDownList>
然而，现在 onCountryChange() 确实触发了，但是 cboCountry 中的值对于 CheckUSAorCAN() 函数来说什么都没有返回。
我没有想法。我该如何完成这项工作？
编辑：如果我在 HTMLSelect 标记上设置 runat="server" 以便我可以从后面的代码访问它，它的作用与 DropDownList 相同，除非我在标记。然后每次选择的值为null，就像DropDownList一样
【问题讨论】：
标签： javascript jquery html asp.net vb.net