如何将复选框值绑定到整数列表? [英] How to bind checkbox values to a list of ints?
问题描述
我正在关注这个例子
但是当我提交时,它说无法将'false'转换为'int'
因为我假设它传递的是 false 或 true,而不是实际值
我做错了什么?
我的模型是
public IEnumerable要求{得到;放;}公共列表RequirementIds { 获取;放;}
那么我的剃须刀是
@foreach(Model.Requirements 中的 var 要求){<div class="row"><input id="@requirement.Id" type="checkbox" name="RequirementIds" value="@requirement.Id"/>@requirement.Description}
您的模型将需要包含选中的值和所有可能的值.
公共类TestViewModel{公共 GUID { 获取;放;}公共 IDictionaryAllCheckboxOptions { 获取;放;}公共 Guid[] CheckedOptions { get;放;}}
我在数据库中使用 Guid 作为 PK,所以这些是数据库中的 ID
然后我创建了一些扩展方法来生成 html
public static MvcHtmlString CheckBoxList(this HtmlHelper htmlHelper, String name, List listInfo,IDictionary<字符串,对象>htmlAttributes,Int32 列){if (String.IsNullOrEmpty(name))throw new ArgumentException("参数必须有值", "name");如果(列表信息 == 空)throw new ArgumentNullException("listInfo");如果 (!listInfo.Any())返回新的 MvcHtmlString(String.Empty);var outerSb = new StringBuilder();for (Int32 i = 0; i <列; i++){var listBuilder = new TagBuilder("ul");如果(列> 1)listBuilder.MergeAttribute("class", "column");var innerSb = new StringBuilder();var take = listInfo.Count % 列 == 0?listInfo.Count/列: (listInfo.Count/列) + 1;var items = listInfo.Skip(i * take).Take(take);foreach(项目中的var信息){var inputBuilder = new TagBuilder("input");if (info.Selected) inputBuilder.MergeAttribute("checked", "checked");inputBuilder.MergeAttribute("type", "checkbox");inputBuilder.MergeAttribute("value", info.Value);inputBuilder.MergeAttribute("id", info.Value);inputBuilder.MergeAttribute("name", info.Value);var labelBuilder = new TagBuilder("label");labelBuilder.MergeAttribute("for", @info.Value);labelBuilder.InnerHtml = info.Text;var listItemWrapper = new TagBuilder("li");//可能需要在这里编码.listItemWrapper.InnerHtml = inputBuilder.ToString(TagRenderMode.SelfClosing) + labelBuilder.ToString(TagRenderMode.Normal);innerSb.Append(listItemWrapper.ToString(TagRenderMode.Normal));}listBuilder.InnerHtml = innerSb.ToString();externalSb.Append(listBuilder.ToString(TagRenderMode.Normal));}返回新的 MvcHtmlString(outerSb.ToString());}
然后在视图中你可以调用你的扩展方法
@Html.CheckBoxList("yourtypes", (来自 Model.AllCheckboxOptions 中的 o选择新的 SelectListItem{文字 = o.Value,Selected = Model.CheckedOptions.Contains(o.Key),值 = o.Key.ToString()}).ToList())
我已经成功地将这种技术用于 MVC3 和 MVC4.
I am following this example
But when I submit, it says can't convert 'false' to 'int'
as I assume its the false or true that is getting passed, not the actual value
what am I doing wrong?
My model is
public IEnumerable<AllocateRequirementViewModel> Requirements { get; set; }
public List<int> RequirementIds { get; set; }
then my razor is
<div id="RequirementsContainer">
@foreach (var requirement in Model.Requirements)
{
<div class="row">
<input id="@requirement.Id" type="checkbox" name="RequirementIds" value="@requirement.Id" /> @requirement.Description
</div>
}
</div>
your model is going to need to contain both the checked values and all the possible values.
public class TestViewModel
{
public Guid Id { get; set; }
public IDictionary<Guid, String> AllCheckboxOptions { get; set; }
public Guid[] CheckedOptions { get; set; }
}
I use Guids as PKs in my database so these are the IDs from the database
I then created a number of extension methods to generate the html
public static MvcHtmlString CheckBoxList(this HtmlHelper htmlHelper, String name, List<SelectListItem> listInfo,
IDictionary<String, Object> htmlAttributes, Int32 columns)
{
if (String.IsNullOrEmpty(name))
throw new ArgumentException("The argument must have a value", "name");
if (listInfo == null)
throw new ArgumentNullException("listInfo");
if (!listInfo.Any())
return new MvcHtmlString(String.Empty);
var outerSb = new StringBuilder();
for (Int32 i = 0; i < columns; i++)
{
var listBuilder = new TagBuilder("ul");
if (columns > 1)
listBuilder.MergeAttribute("class", "column");
var innerSb = new StringBuilder();
var take = listInfo.Count % columns == 0
? listInfo.Count / columns
: (listInfo.Count / columns) + 1;
var items = listInfo.Skip(i * take).Take(take);
foreach (var info in items)
{
var inputBuilder = new TagBuilder("input");
if (info.Selected) inputBuilder.MergeAttribute("checked", "checked");
inputBuilder.MergeAttribute("type", "checkbox");
inputBuilder.MergeAttribute("value", info.Value);
inputBuilder.MergeAttribute("id", info.Value);
inputBuilder.MergeAttribute("name", info.Value);
var labelBuilder = new TagBuilder("label");
labelBuilder.MergeAttribute("for", @info.Value);
labelBuilder.InnerHtml = info.Text;
var listItemWrapper = new TagBuilder("li");
//may have to encode here.
listItemWrapper.InnerHtml = inputBuilder.ToString(TagRenderMode.SelfClosing) + labelBuilder.ToString(TagRenderMode.Normal);
innerSb.Append(listItemWrapper.ToString(TagRenderMode.Normal));
}
listBuilder.InnerHtml = innerSb.ToString();
outerSb.Append(listBuilder.ToString(TagRenderMode.Normal));
}
return new MvcHtmlString(outerSb.ToString());
}
then in the view you can call your extension method
@Html.CheckBoxList("yourtypes", (from o in Model.AllCheckboxOptions
select new SelectListItem
{
Text = o.Value,
Selected = Model.CheckedOptions.Contains(o.Key),
Value = o.Key.ToString()
}).ToList())
I've used this technique with both MVC3 and MVC4 with success.
这篇关于如何将复选框值绑定到整数列表?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!