강좌 - asp.net mvc 패턴




누구든지 ASP.NET MVC에 대한 RadioButtonListFor<T>를 구현 했습니까? (5)

ASP.NET MVC Futures에는 Html.RadioButtonList 확장 메서드가있었습니다. 누구든지 강력하게 형식화 된 버전 인 RadioButtonListFor<T> 대한 코드를 찾았습니까? 보기에서 다음과 같이 보입니다.

<%= Html.RadioButtonListFor(model=>model.Item,Model.ItemList) %>

1 옵션이 선택되었는지 확인하기 위해 유효성 검사와 함께 3 개의 라디오 버튼을 만드는 MVC 3 예제입니다. 양식이 유효성 검사에 실패하면 (예 : 다른 필드에서) 양식을 다시 표시 할 때 선택한 라디오 옵션이 미리 선택됩니다.

전망

@Html.RadioButtonForSelectList(m => m.TestRadio, Model.TestRadioList)
@Html.ValidationMessageFor(m => m.TestRadio)

모델

public class aTest
{
    public Int32 ID { get; set; }
    public String Name { get; set; }
}

public class LogOnModel
{
    public IEnumerable<SelectListItem> TestRadioList { get; set; }

    [Required(ErrorMessage="Test Error")]
    public String TestRadio { get; set; }

    [Required]
    [Display(Name = "User name")]
    public string UserName { get; set; }
}

컨트롤러 동작

public ActionResult LogOn()
    {
        List<aTest> list = new List<aTest>();
        list.Add(new aTest() { ID = 1, Name = "Line1" });
        list.Add(new aTest() { ID = 2, Name = "Line2" });
        list.Add(new aTest() { ID = 3, Name = "Line3" });

        SelectList sl = new SelectList(list, "ID", "Name");

        var model = new LogOnModel();
        model.TestRadioList = sl;

        return View(model);
    }

    [HttpPost]
    public ActionResult LogOn(LogOnModel model, string returnUrl)
    {
        if (ModelState.IsValid)
        {
             ....
        }

        // If we got this far, something failed, redisplay form
        List<aTest> list = new List<aTest>();
        list.Add(new aTest() { ID = 1, Name = "Line1" });
        list.Add(new aTest() { ID = 2, Name = "Line2" });
        list.Add(new aTest() { ID = 3, Name = "Line3" });

        SelectList sl = new SelectList(list, "ID", "Name");
        model.TestRadioList = sl;

        return View(model);
    }

확장 기능은 다음과 같습니다.

public static class HtmlExtensions
{
    public static MvcHtmlString RadioButtonForSelectList<TModel, TProperty>(
        this HtmlHelper<TModel> htmlHelper,
        Expression<Func<TModel, TProperty>> expression,
        IEnumerable<SelectListItem> listOfValues)
    {
        var metaData = ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData);
        var sb = new StringBuilder();

        if (listOfValues != null)
        {
            foreach (SelectListItem item in listOfValues)
            {
                var id = string.Format(
                    "{0}_{1}",
                    metaData.PropertyName,
                    item.Value
                );

                var radio = htmlHelper.RadioButtonFor(expression, item.Value, new { id = id }).ToHtmlString();
                sb.AppendFormat(
                    "<label for=\"{0}\">{1}</label> {2}",
                    id,
                    HttpUtility.HtmlEncode(item.Text),
                    radio
                );
            }
        }

        return MvcHtmlString.Create(sb.ToString());
    }
}

나는 MVC 1.0에서 비슷한 것을 구현했다. 이것이 당신에게 도움이되는지보기 :

    public static string RadioButtonList2(this HtmlHelper _helper, string _name, IEnumerable<SelectListItem> _items, string _selectedValue, string _seperator)
    {
        return RadioButtonList2(_helper, _name, _items, _selectedValue, _seperator, null);
    }

    public static string RadioButtonList2(this HtmlHelper _helper, string _name, IEnumerable<SelectListItem> _items, string _selectedValue, string _seperator, IDictionary<string, object> _htmlAttributes)
    {
        StringBuilder _outputScript = new StringBuilder();

        foreach (var item in _items)
        {
            var optionField = new TagBuilder("input");
            optionField.MergeAttribute("name", _name);
            optionField.MergeAttribute("id", _name);
            optionField.MergeAttribute("class", _name);
            optionField.MergeAttribute("value", item.Value);
            optionField.MergeAttribute("type", "radio");

            // Check to see if it's checked
            if (item.Value == _selectedValue)
                optionField.MergeAttribute("checked", "checked");

            if (_htmlAttributes != null)
                optionField.MergeAttributes(_htmlAttributes);

            _outputScript.Append(optionField.ToString(TagRenderMode.SelfClosing));
            _outputScript.Append("<label style=\"display:inline;\">");
            _outputScript.Append(item.Text);
            _outputScript.Append("</label>" + _seperator);
        }

        return _outputScript.ToString();
    }

컨트롤러에서 다음과 같이 결과를 반환 할 수 있습니다.

        ViewData["GenderList"] = new SelectList(new[] { new { Value = "M", Text = "Male" }, new { Value = "F", Text = "Female" }, new { Value = "A", Text = "All" } }, "Value", "Text");

또는

        ViewData["GenderList"] = new SelectList(_resultFromSomeLinqQuery, "GenderID", "GenderName");

보기에서 다음과 같이 사용하십시오.

<%= Html.RadioButtonList2("Sex", ViewData["GenderList"] as SelectList, ViewData["SelectedSex"].ToString(), "&nbsp;")%>

또한 &nbsp; <BR /> 를 사용하여 별도의 줄에 표시하십시오.

희망이 도움이됩니다.

감사합니다 Naweed Akram [email protected]


다음은 aspx 페이지의 사용법입니다.

    <%= Html.RadioButtonListFor(m => m.GenderRadioButtonList)%>

다음은 뷰 모델입니다.

public class HomePageViewModel
{
    public enum GenderType
    {
        Male,
        Female
    }
    public RadioButtonListViewModel<GenderType> GenderRadioButtonList { get; set; }

    public HomePageViewModel()
    {
        GenderRadioButtonList = new RadioButtonListViewModel<GenderType>
        {
            Id = "Gender",
            SelectedValue = GenderType.Male,
            ListItems = new List<RadioButtonListItem<GenderType>>
            {
                new RadioButtonListItem<GenderType>{Text = "Male", Value = GenderType.Male},
                new RadioButtonListItem<GenderType>{Text = "Female", Value = GenderType.Female}
            }
        };
    }
}

라디오 버튼 목록에 사용되는보기 모델은 다음과 같습니다.

public class RadioButtonListViewModel<T>
{
    public string Id { get; set; }
    private T selectedValue;
    public T SelectedValue
    {
        get { return selectedValue; }
        set
        {
            selectedValue = value;
            UpdatedSelectedItems();
        }
    }

    private void UpdatedSelectedItems()
    {
        if (ListItems == null)
            return;

        ListItems.ForEach(li => li.Selected = Equals(li.Value, SelectedValue));
    }

    private List<RadioButtonListItem<T>> listItems;
    public List<RadioButtonListItem<T>> ListItems
    {
        get { return listItems; }
        set
        {
            listItems = value;
            UpdatedSelectedItems();
        }
    }
}

public class RadioButtonListItem<T>
{
    public bool Selected { get; set; }

    public string Text { get; set; }

    public T Value { get; set; }

    public override string ToString()
    {
        return Value.ToString();
    }
}

RadioButtonListFor의 확장 메소드는 다음과 같습니다.

public static class HtmlHelperExtensions
{
    public static string RadioButtonListFor<TModel, TRadioButtonListValue>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, RadioButtonListViewModel<TRadioButtonListValue>>> expression) where TModel : class
    {
        return htmlHelper.RadioButtonListFor(expression, null);
    }

    public static string RadioButtonListFor<TModel, TRadioButtonListValue>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, RadioButtonListViewModel<TRadioButtonListValue>>> expression, object htmlAttributes) where TModel : class
    {
        return htmlHelper.RadioButtonListFor(expression, new RouteValueDictionary(htmlAttributes));
    }

    public static string RadioButtonListFor<TModel, TRadioButtonListValue>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, RadioButtonListViewModel<TRadioButtonListValue>>> expression, IDictionary<string, object> htmlAttributes) where TModel : class
    {
        var inputName = GetInputName(expression);

        RadioButtonListViewModel<TRadioButtonListValue> radioButtonList = GetValue(htmlHelper, expression);

        if (radioButtonList == null)
            return String.Empty;

        if (radioButtonList.ListItems == null)
            return String.Empty;

        var divTag = new TagBuilder("div");
        divTag.MergeAttribute("id", inputName);
        divTag.MergeAttribute("class", "radio");
        foreach (var item in radioButtonList.ListItems)
        {
            var radioButtonTag = RadioButton(htmlHelper, inputName, new SelectListItem{Text=item.Text, Selected = item.Selected, Value = item.Value.ToString()}, htmlAttributes);

            divTag.InnerHtml += radioButtonTag;
        }

        return divTag + htmlHelper.ValidationMessage(inputName, "*");
    }

    public static string GetInputName<TModel, TProperty>(Expression<Func<TModel, TProperty>> expression)
    {
        if (expression.Body.NodeType == ExpressionType.Call)
        {
            var methodCallExpression = (MethodCallExpression)expression.Body;
            string name = GetInputName(methodCallExpression);
            return name.Substring(expression.Parameters[0].Name.Length + 1);

        }
        return expression.Body.ToString().Substring(expression.Parameters[0].Name.Length + 1);
    }

    private static string GetInputName(MethodCallExpression expression)
    {
        // p => p.Foo.Bar().Baz.ToString() => p.Foo OR throw...

        var methodCallExpression = expression.Object as MethodCallExpression;
        if (methodCallExpression != null)
        {
            return GetInputName(methodCallExpression);
        }
        return expression.Object.ToString();
    }

    public static string RadioButton(this HtmlHelper htmlHelper, string name, SelectListItem listItem,
                         IDictionary<string, object> htmlAttributes)
    {
        var inputIdSb = new StringBuilder();
        inputIdSb.Append(name)
            .Append("_")
            .Append(listItem.Value);

        var sb = new StringBuilder();

        var builder = new TagBuilder("input");
        if (listItem.Selected) builder.MergeAttribute("checked", "checked");
        builder.MergeAttribute("type", "radio");
        builder.MergeAttribute("value", listItem.Value);
        builder.MergeAttribute("id", inputIdSb.ToString());
        builder.MergeAttribute("name", name + ".SelectedValue");
        builder.MergeAttributes(htmlAttributes);
        sb.Append(builder.ToString(TagRenderMode.SelfClosing));
        sb.Append(RadioButtonLabel(inputIdSb.ToString(), listItem.Text, htmlAttributes));
        sb.Append("<br>");

        return sb.ToString();
    }

    public static string RadioButtonLabel(string inputId, string displayText,
                                 IDictionary<string, object> htmlAttributes)
    {
        var labelBuilder = new TagBuilder("label");
        labelBuilder.MergeAttribute("for", inputId);
        labelBuilder.MergeAttributes(htmlAttributes);
        labelBuilder.InnerHtml = displayText;

        return labelBuilder.ToString(TagRenderMode.Normal);
    }


    public static TProperty GetValue<TModel, TProperty>(HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, TProperty>> expression) where TModel : class
    {
        TModel model = htmlHelper.ViewData.Model;
        if (model == null)
        {
            return default(TProperty);
        }
        Func<TModel, TProperty> func = expression.Compile();
        return func(model);
    }
}

여기 좋은 VB에서 slighly 'slimmer'답변이 있습니다. 나를 위해 작동하지만 완벽한 해결책은 아닙니다.

<Extension()> _
Public Function RadioButtonListFor(Of TModel, TProperty)(ByVal htmlHelper As System.Web.Mvc.HtmlHelper(Of TModel), ByVal expression As System.Linq.Expressions.Expression(Of System.Func(Of TModel, TProperty)), ByVal selectList As System.Collections.Generic.IEnumerable(Of System.Web.Mvc.SelectListItem), ByVal htmlAttributes As Object) As System.Web.Mvc.MvcHtmlString
    'Return htmlHelper.DropDownListFor(expression, selectList, htmlAttributes)
    If selectList Is Nothing OrElse selectList.Count = 0 Then Return MvcHtmlString.Empty

    Dim divTag = New TagBuilder("div")
    divTag.MergeAttributes(New RouteValueDictionary(htmlAttributes))
    Dim name = CType(expression.Body, System.Linq.Expressions.MemberExpression).Member.Name
    Dim value = expression.Compile()(htmlHelper.ViewData.Model)
    Dim sb As New StringBuilder()

    For Each item In selectList
        sb.AppendFormat("<input id=""{0}_{1}"" type=""radio"" name=""{0}"" value=""{1}"" {2} />", name, item.Value, If(item.Value = value.ToString, """checked""", ""))
        sb.AppendFormat("<label for=""{0}_{1}"">{2}</label>", name, item.Value, item.Text)
    Next

    divTag.InnerHtml = sb.ToString

    Return MvcHtmlString.Create(divTag.ToString)

End Function

Jon 포스트를 기반으로 HTMLAttributtes를 사용하여 라디오 버튼 목록을 ul로 생성하는 기능이 향상되었습니다.

public static MvcHtmlString RadioButtonListFor<TModel, TProperty>(
        this HtmlHelper<TModel> htmlHelper,
        Expression<Func<TModel, TProperty>> expression,
        IEnumerable<SelectListItem> listOfValues,
        IDictionary<string, object> radioHtmlAttributes = null,
        string ulClass = null)
    {
        ModelMetadata metaData = ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData);

        if (radioHtmlAttributes == null)
            radioHtmlAttributes = new RouteValueDictionary();

        TagBuilder ulTag = new TagBuilder("ul");
        if (!String.IsNullOrEmpty(ulClass))
            ulTag.MergeAttribute("class", ulClass);

        if (listOfValues != null)
        {
            // Create a radio button for each item in the list 
            foreach (SelectListItem item in listOfValues)
            {

                // Generate an id to be given to the radio button field 
                var id = string.Format("{0}_{1}", metaData.PropertyName, item.Value);

                if (!radioHtmlAttributes.ContainsKey("id"))
                    radioHtmlAttributes.Add("id", id);
                else
                    radioHtmlAttributes["id"] = id;

                // Create and populate a radio button using the existing html helpers 
                var label = htmlHelper.Label(id, HttpUtility.HtmlEncode(item.Text));
                var radio = htmlHelper.RadioButtonFor(expression, item.Value, radioHtmlAttributes).ToHtmlString();

                // Create the html string that will be returned to the client 
                // e.g. <input data-val="true" data-val-required="You must select an option" id="TestRadio_1" name="TestRadio" type="radio" value="1" /><label for="TestRadio_1">Line1</label> 
                ulTag.InnerHtml += string.Format("<li>{0}{1}</li>", radio, label);
            }
        }

        return MvcHtmlString.Create(ulTag.ToString(TagRenderMode.Normal));
    }

    public static MvcHtmlString RadioButtonListFor<TModel, TProperty>(
        this HtmlHelper<TModel> htmlHelper,
        Expression<Func<TModel, TProperty>> expression,
        IEnumerable<SelectListItem> listOfValues,
        object radioHtmlAttributes = null,
        string ulClass = null)
    {
        return RadioButtonListFor<TModel, TProperty>(htmlHelper, expression, listOfValues, new RouteValueDictionary(radioHtmlAttributes), ulClass);
    }




asp.net-mvc-2