javascript - 如何使用 JavaScript 插入新的表单行并将其包含在传递给 Controller ​​的内容中？

Question

上下文

ASP.NET Core 2.0 MVC/EF Core/C#

问题

我有一个 View ，用于创建新的父行和关联的子行，后者位于 html 表中。最初显示一个空白子行。这一切都被提交给创建 Controller 操作来处理数据库添加，并且工作正常。编码如下:

@using DBWTools.ViewModels
@model IssueViewModel

@section css {
    <link rel="stylesheet" href="//code.jquery.com/ui/1.12.1/themes/base/jquery-ui.css" />
}

<h2>New Issue</h2>

<hr />

<form asp-controller="Home" asp-action="CreateIssue" method="post" id="CreateIssueForm">
    <div asp-validation-summary="All" class="text-danger"></div>

    @* Parent row coding goes here. Removed for brevity *@

    <div class="row">
        <div class="col-md-12">
            <table class="table table-bordered table-striped table-hover">
                <thead>
                    <tr>
                        <th class="col-md-1">Date</th>
                        <th class="col-md-10">Comment</th>
                        <th class="col-md-1">
                            <button type="button" onclick="appendIssueComment()" class="btn btn-primary"
                                    data-toggle="tooltip" title="Add another comment">
                                <span class="glyphicon glyphicon-plus" />
                            </button>
                        </th>
                    </tr>
                </thead>
                <tbody class="commentBody">
                    @for (int i = 0; i < Model.Comments.Count; i++)
                    {
                        <tr class="commentRow">
                            <td>
                                <input asp-for="@Model.Comments[i].DateCreated" class="form-control" type="date" asp-format="{0:yy-MM-dd}" />
                            </td>
                            <td>
                                <textarea asp-for="@Model.Comments[i].Narrative" class="form-control"></textarea>
                            </td>
                            <td style="display:none"><input asp-for="@Model.Comments[i].ID" type="hidden" /></td>
                        </tr>
                    }
                </tbody>
            </table>
        </div>
    </div>
    <div class="row">
        <div class="form-horizontal">
            <div class="col-md-1">
                <button type="submit" class="btn btn-primary">Create</button>
            </div>
        </div>
    </div>
</form>

@section Scripts {
    <script src="https://code.jquery.com/ui/1.12.1/jquery-ui.js"></script>

    @await Html.PartialAsync("_ValidationScriptsPartial")
    <script src="~/js/AppendIssueComment.js" type="text/javascript"></script>
}

该表包含一个带有 onClick 操作的按钮，该操作运行 JavaScript 函数以向表中添加额外的行。其功能是:

function appendIssueComment() {

    $(".commentBody").append("<tr>" +
                                "<td><input class='form-control' type='date' data-val='true' data-val-required='The Date created field is required.' id='Comments_0__DateCreated' name='Comments[0].DateCreated' value=''/></td >" +
                                "<td><textarea class='form-control' data-val='true' data-val-required = 'The Narrative field is required.' id='Comments_0__Narrative' name='Comments[0].Narrative'></textarea></td >" +
                                "<td style = 'display:none'><input type='hidden' data-val='true' data-val-required='The ID field is required.' id='Comments_0__ID' name='Comments[0].ID' value='0'/></td > " +
                            "</tr >");
}

这成功添加了新的空白行，并且可以将数据键入其中。但是，当提交表单时，新行不会传递到 Controller 。

问题

如何向 HTML 表添加新行并将它们成功传递到 Controller ？

编辑

根据@tchelidze 解决方案更新了函数

function appendIssueComment() {

    var lastRow = $("[id$='__ID']").length.toString();

    $(".commentBody").append("<tr>" +
                                "<td><input class='form-control' type='date' data-val='true' data-val-required='The Date created field is required.' id='Comments_" + lastRow + "__DateCreated' name='Comments[" + lastRow + "].DateCreated' value=''/></td >" +
                                "<td><textarea class='form-control' data-val='true' data-val-required = 'The Narrative field is required.' id='Comments_" + lastRow + "__Narrative' name='Comments[" + lastRow + "].Narrative'></textarea></td >" +
                                "<td style = 'display:none'><input type='hidden' data-val='true' data-val-required='The ID field is required.' id='Comments_" + lastRow + "__ID' name='Comments[" + lastRow + "].ID' value='0'/></td > " +
                            "</tr >");
}

Answer 1

新行始终绑定(bind)到 Comments[0] 元素，您必须增加每行的索引。