站在@dotnetstep 和@gsxrboy73 的肩膀上，这种方法添加了一个可选的控件标题和“全选”类型的复选框。它还序列化“id”属性，因此您可以安全地在页面上拥有多个复选框列表。这是为 .NET 5 绑定到 Bootstrap 环境中的 MVC 模型量身定制的。
我更喜欢不包含在巨型 mvc 库中的轻薄模型：
public class CheckBoxListItem
{
public string Key { get; set; }
public string Value { get; set; }
public bool IsChecked { get; set; } = false;
public bool IsDisabled { get; set; } = false;
}
List<CheckBoxListItem> 驱动 Tag Helper：
/// <summary>check-box-list Tag Helper</summary>
[HtmlTargetElement("Check-Box-List", Attributes = "asp-title, asp-items, asp-model-name, asp-check-all-label", TagStructure=TagStructure.NormalOrSelfClosing)]
public class CheckBoxListTagHelper : TagHelper
{
/// <summary>HTML element ID of the tracking form element</summary>
[HtmlAttributeName("asp-form-id")]
public string FormId { get; set; }
/// <summary>Optional bolder title set above the check box list</summary>
[HtmlAttributeName("asp-title")]
public string ListTitle { get; set; }
/// <summary>List of individual child/item values to be rendered as check boxes</summary>
[HtmlAttributeName("asp-items")]
public List<CheckBoxListItem> Items { get; set; }
/// <summary>The name of the view model which is used for rendering html "id" and "name" attributes of each check box input.
/// Typically the name of a List[CheckBoxListItem] property on the actual passed in @Model</summary>
[HtmlAttributeName("asp-model-name")]
public string ModelName { get; set; }
/// <summary>Optional label of a "Check All" type checkbox. If left empty, a "Check All" check box will not be rendered.</summary>
[HtmlAttributeName("asp-check-all-label")]
public string CheckAllLabel { get; set; }
public override void Process(TagHelperContext context, TagHelperOutput output)
{
string id = context.UniqueId;
output.TagName = "div";
string html = "";
output.PreElement.AppendHtml($"<!-- Check List Box for {(string.IsNullOrEmpty(ListTitle) ? ModelName : ListTitle)} -->\r\n");
if (!string.IsNullOrEmpty(ListTitle))
{
// Prepend a Title to the control
output.PreContent.AppendHtml($"\r\n\t<label id=\"check-box-list-label-{id}\" class=\"cblTitle\">\r\n"
+ $"\t\t<strong>{ListTitle}</strong>\r\n"
+ $"\t</label>\r\n");
}
if (!string.IsNullOrEmpty(CheckAllLabel))
{
// Prepend a "Check All" type checkbox to the control
output.PreContent.AppendHtml("\t<div class=\"form-check\">\r\n"
+ $"\t\t<input id=\"check-box-list-all-{id}\"\r\n"
+ "\t\t\tclass=\"cblCheckAllInput form-check-input\"\r\n"
+ "\t\t\ttype=\"checkbox\"\r\n"
+ $"\t\t\tvalue=\"true\"\r\n"
);
if (Items.All(cbli => cbli.IsChecked))
{
output.PreContent.AppendHtml("\t\t\tchecked=\"checked\"\r\n");
}
output.PreContent.AppendHtml("\t\t\t/>\r\n"
+ $"\t\t<label id=\"check-box-list-all-label-{id}\" class=\"cblCheckAllLabel form-check-label\" for=\"check-box-list-all-{id}\">\r\n"
+ $"\t\t\t {CheckAllLabel}\r\n"
+ "\t\t</label>\r\n"
+ "\t</div>\r\n"
) ;
}
// Begin the actual Check Box List control
output.Content.AppendHtml($"\t<div id=\"cblContent-{id}\" class=\"cblContent\">\r\n");
// Create an individual check box for each item
for (int i = 0; i < Items.Count(); i++)
{
CheckBoxListItem item = Items[i];
html = "\t\t<div class=\"form-check\">\r\n"
+ $"\t\t\t<input id=\"{ModelName}_{i}__IsChecked-{id}\"\r\n"
+ $"\t\t\t\tname=\"{ModelName}[{i}].IsChecked\"\r\n"
+ $"\t\t\t\tclass=\"cblCheckBox form-check-input\"\r\n"
+ $"\t\t\t\tform=\"{FormId}\"\r\n"
+ "\t\t\t\tdata-val=\"true\"\r\n"
+ "\t\t\t\ttype=\"checkbox\""
+ "\t\t\t\tvalue=\"true\""
;
if (item.IsChecked)
{
html += "\t\t\t\tchecked=\"checked\"\r\n";
}
if (item.IsDisabled)
{
html += "\t\t\t\tdisabled=\"disabled\"\r\n";
}
html += "\t\t\t\t/>\r\n"
+ $"\t\t\t<label id=\"check-box-list-item-label-{id}-{i}\" class=\"cblItemLabel form-check-label\" for=\"{ModelName}_{i}__IsChecked-{id}\">\r\n"
+ $"\t\t\t\t {item.Value}\r\n"
+ "\t\t\t</label>\r\n"
+ $"\t\t\t<input type=\"hidden\" id=\"{ModelName}_{i}__IsChecked-{id}-tag\" name=\"{ModelName}[{i}].IsChecked\" form =\"{FormId}\" value=\"false\">\r\n"
+ $"\t\t\t<input type=\"hidden\" id=\"{ModelName}_{i}__Key-{id}\" name=\"{ModelName}[{i}].Key\" form =\"{FormId}\" value=\"{item.Key}\">\r\n"
+ $"\t\t\t<input type=\"hidden\" id=\"{ModelName}_{i}__Value-{id}\" name=\"{ModelName}[{i}].Value\" form =\"{FormId}\" value=\"{item.Value}\">\r\n"
+ "\t\t</div>\r\n"
;
output.Content.AppendHtml(html);
}
output.Content.AppendHtml("\t</div>\r\n");
output.Attributes.SetAttribute("id", $"check-box-list-{id}");
output.Attributes.SetAttribute("class", "cblCheckBoxList");
}
}
揭示原型 JS 使“检查所有”框与其他框相得益彰：
// Attach event handlers to controls
$(function () {
// Toggle child check boxes per the "Check All" check box state
$("div.cblCheckBoxList").on("click", "input.cblCheckAllInput", function (event) {
let chkBoxListDiv = $(event.target).closest("div.cblCheckBoxList");
let chkBoxList = new checkBoxList($(chkBoxListDiv).attr("id"), $(event.target).attr("id"));
chkBoxList.onCheckAllClick();
});
// Sync the "Check All" box w/ the child check boxes' check box states
$("div.cblCheckBoxList").on("click", "input.cblCheckBox", function (event) {
let chkBoxListDiv = $(event.target).closest("div.cblCheckBoxList");
let chkBoxList = new checkBoxList($(chkBoxListDiv).attr("id"), null);
chkBoxList.onCheckItemClick();
});
});
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//
// Check Box List
//
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
var checkBoxList = function (checkBoxListDivId, checkAllInputId) {
this.listDivId = checkBoxListDivId;
this.allInputId = (checkAllInputId ?? $("#" + this.listDivId).find("input.cblCheckAllInput")?.first()?.attr("id"));
};
checkBoxList.prototype = function () {
// If a "Check All" type check box is clicked, update the individual child check boxes accordingly
var onCheckAllClick = function () {
// Find the "Check All" check box that was clicked
let checkAllInput = $('#' + this.allInputId);
// Determine whether the "Check All" check box is checked or unchecked
let chkd = $(checkAllInput).prop('checked');
// Get a list of child/item check boxes
let chks = $('#' + this.listDivId).find('input.cblCheckBox');
// Make the child/item check boxes match the value of the "Check All" check box
chks.prop('checked', chkd);
},
// If an individual child check box is clicked and a "Check All" type checkbox exists, update it accordingly
onCheckItemClick = function () {
if (!((this.allInputId === undefined) || (this.allInputId.length === 0))) {
// Get an array of check boxes that are NOT checked
let notChkd = $('#' + this.listDivId).find("input.cblCheckBox:not(:checked)");
// Update the "Check All" check box accordingly
$("#" + this.allInputId).prop('checked', (notChkd.length === 0));
}
};
return {
onCheckAllClick: onCheckAllClick,
onCheckItemClick: onCheckItemClick
};
}();
涂上一些 CSS 口红：
/* For CheckBoxList form control */
.cblCheckBoxList {
border: 1px solid #ccc;
padding: 10px 15px;
margin-right: 10px;
-webkit-border-radius: 5px;
-moz-border-radius: 5px;
-ms-border-radius: 5px;
border-radius: 5px;
}
.cblCheckBoxList .cblContent {
height: 150px;
overflow-y: scroll;
padding: 0;
margin: 0;
}
.cblCheckBoxList .cblTitle {
font-weight: bolder;
}
.cblCheckBoxList .cblCheckAllLabel {
margin-bottom: 10px;
}
.cblCheckBoxList .cblCheckAllInput {
margin-bottom: 0;
}
.cblCheckBoxList .cblItemLabel {
margin-bottom: 0;
font-size: small;
}
.cblCheckBoxList .cblCheckBox {
margin-bottom: 0;
font-size: small;
}
然后将复选框列表拖放到页面上：
@* On the passed in View Model, "IceCreamFlavors" is a property that is a List of type CheckBoxListItem *@
<check-box-list
asp-title="Ice Cream Flavors"
asp-items="Model.IceCreamFlavors"
asp-model-name="IceCreamFlavors"
asp-form-id="my-form-id"
asp-check-all-label="All Flavors"
>
</check-box-list>
博塔繁荣，博塔兵。