Question

我试图创建一个页面来编辑“人物”，但是我在如何编辑List对象方面遇到了麻烦（并且通过编辑，我的意思是如何动态添加一封电子邮件到列表）。在线研究和stackoverflow研究使我进入EditorTemplates，然后使用ajax动态添加项目。但是，我错过了某个地方的联系。要么为新电子邮件创建未绑定的空文本框，要么获取空引用错误。

型号：

[DynamoDBTable("people")]
public class Person
{
    [DynamoDBHashKey]
    [DynamoDBProperty(AttributeName = "name")]
    public string Name{ get; set; }

    [DynamoDBRangeKey]
    [DynamoDBProperty(AttributeName = "id")]
    public string ID { get; set; }

    [DynamoDBProperty(AttributeName = "emails")]
    public List<string> Emails{ get; set; }

    public Person()
    {

    }
}

查看：

<div id="emails" class="row">
    <div class="form-group col-xs-6 col-sm-6">
        @Html.LabelFor(x => x.Emails)
        @Html.EditorFor(x => Model.Emails, new { @class = "form-control"})
    </div>
    <button id="addEmail">Add</button>
</div> 

<script type="text/javascript">
        $("#addEmail").on('click', function (event) {
            event.preventDefault();
            $.ajax({
                async: false,
                url: '/controller/newEmail'
            }).success(function (partialView) {
                $('#emails').append(partialView);
            });
        });
</script>

EditorTemplate - 人：

@model Models.Person

@for (int i = 0; i < Model.Emails.Count(); i++)
{
    @Html.EditorFor(x => Model.Emails)

}

EditorTemplate - String：

@model string

@Html.TextBoxFor(model => Model)

控制器：

public ActionResult newEmail()
{
    var emails = new Person().Emails;

    return PartialView("~/Views/Shared/EditorTemplates/string.cshtml", emails);
}

Answer 1

您的Person.Emails对象为空且尚未初始化

public ActionResult newEmail()
{
    var emails = new Person().Emails;

    return PartialView("~/Views/Shared/EditorTemplates/string.cshtml", emails);
}

将其更改为：

public ActionResult newEmail()
{
    var emails = new Person().Emails = new List<string>();

    return PartialView("~/Views/Shared/EditorTemplates/string.cshtml", emails);
}

编辑List <string> MVC 4的表单

1 个答案: