C# 为IEnumerable创建HiddenFor<；字符串>；鉴于_C#_Asp.net Mvc_Asp.net Mvc 3_Linq_Entity

C# 为IEnumerable创建HiddenFor<；字符串>；鉴于

c# asp.net-mvc asp.net-mvc-3 linq

C# 为IEnumerable创建HiddenFor<；字符串>；鉴于,c#,asp.net-mvc,asp.net-mvc-3,linq,entity,C#,Asp.net Mvc,Asp.net Mvc 3,Linq,Entity,我有一个属性是IEnumerable public IEnumerable<string> ChangesOthersResult { get; set; } 正在将原始SQL语句作为文本提供给我在模型的构造函数中，新建IEnumerable ChagesOthersResult public Model () { ChangesOthersResult = new List<string>(); } 公共模型（） { ChangesOthersResult=新

我有一个属性是IEnumerable

public IEnumerable<string> ChangesOthersResult { get; set; }

正在将原始SQL语句作为文本提供给我

在模型的构造函数中，新建IEnumerable ChagesOthersResult

public Model ()
{
  ChangesOthersResult = new List<string>();
}

公共模型（）
{
ChangesOthersResult=新列表（）；
}

然后在视图中，使用for循环

for(int i = 0; i < Model.ChangesOthersResult.Count; i++)
{
  @Html.HiddenFor(x => x.ChangesOthersResult[i])
}

for（int i=0；ix.ChangesOthersResult[i]）
}

将ChangeSotherResult转换为数组，并使用for循环输出如下内容：

for (int i = 0; i < Model.ChangesOthersResult.Length; i++ )    
{
   @Html.Hidden("ChangesOthersResult[" + i + "]", Model.ChangesOthersResult[i])
}

for（int i=0；i

我将其制作成一个扩展方法，这样for循环就不会丑化您的视图代码：

public static class HiddenExtensions
{
    public static MvcHtmlString HiddenForEnumerable<TModel, TProperty>(this HtmlHelper<TModel> helper,
        Expression<Func<TModel, IEnumerable<TProperty>>> expression)

    {
        var sb = new StringBuilder();

        var membername = expression.GetMemberName();
        var model = helper.ViewData.Model;
        var list = expression.Compile()(model);

        for (var i = 0; i < list.Count(); i++)
        {
            sb.Append(helper.Hidden(string.Format("{0}[{1}]", membername, i), list.ElementAt(i)));
        }

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

公共静态类HiddenExtensions
{
公共静态MvcHtmlString HiddenForEnumerable（此HtmlHelper，
表达式（表达式）
{
var sb=新的StringBuilder（）；
var membername=expression.GetMemberName（）；
var model=helper.ViewData.model；
var list=expression.Compile（）（模型）；
对于（var i=0；i


GetMemberName是另一个扩展方法：
    public static string GetMemberName<TModel, T>(this Expression<Func<TModel, T>> input)
    {
        if (input == null)
            return null;

        if (input.Body.NodeType != ExpressionType.MemberAccess)
            return null;

        var memberExp = input.Body as MemberExpression;
        return memberExp != null ? memberExp.Member.Name : null;
    }

公共静态字符串GetMemberName（此表达式输入）
{
如果（输入==null）
返回null；
if（input.Body.NodeType！=ExpressionType.MemberAccess）
返回null；
var memberExp=input.Body作为MemberExpression；
return memberExp！=null？memberExp.Member.Name:null；
}

希望这是有帮助的
 无法使用.ForEach（），因为@Html.HiddenFor（x=>x.changeSotherResult）将创建相同的元素ID，模型在回发时无法识别该ID
for (int i = 0; i < Model.ChangesOthersResult.Count(); i++ )    
{
    @Html.HiddenFor(x => x.ChangesOthersResult[I]);
}

for（int i=0；ix.ChangesOthersResult[I]）；
}
针对自定义对象列表的扩展@GitteTitter解决方案：
@Html.HiddenForEnumerable(x => x.ValueTypes)    
@Html.HiddenForEnumerable(x => x.ViewModels, h=>h.Id, h=>h.Name)
@Html.HiddenForEnumerable(x => x.ViewModels, allPublicProps: true)

资料来源：
/// <summary>
/// Returns hiddens for every IEnumerable item, with it's selected properties, if any memberPropsExpression provided.
/// </summary>
public static MvcHtmlString HiddenForEnumerable<TModel, TModelProperty>(this HtmlHelper<TModel> helper,
    Expression<Func<TModel, IEnumerable<TModelProperty>>> expression, params Expression<Func<TModelProperty, object>>[] memberPropsExpressions)
{
    var sb = new StringBuilder();

    var membername = expression.GetMemberName();
    var model = helper.ViewData.Model;
    var list = expression.Compile()(model);

    var memPropsInfo = memberPropsExpressions.Select(x => new
    {
        MemberPropName = x.GetMemberName(),
        ListItemPropGetter = x.Compile()
    }).ToList();

    for (var i = 0; i < list.Count(); i++)
    {
        var listItem = list.ElementAt(i);
        if (memPropsInfo.Any())
        {
            foreach (var q in memPropsInfo)
            {
                sb.Append(helper.Hidden(string.Format("{0}[{1}].{2}", membername, i, q.MemberPropName), q.ListItemPropGetter(listItem)));
            }
        }
        else
        {
            sb.Append(helper.Hidden(string.Format("{0}[{1}]", membername, i), listItem));
        }
    }

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

/// <summary>
/// Returns hiddens for every IEnumerable item, with it's all public writable properties, if allPublicProps set to true.
/// </summary>
public static MvcHtmlString HiddenForEnumerable<TModel, TModelProperty>(this HtmlHelper<TModel> helper,
   Expression<Func<TModel, IEnumerable<TModelProperty>>> expression, bool allPublicProps)
{
    if (!allPublicProps)
        return HiddenForEnumerable(helper, expression);

    var sb = new StringBuilder();

    var membername = expression.GetMemberName();
    var model = helper.ViewData.Model;
    var list = expression.Compile()(model);

    var type = typeof(TModelProperty);
    var memPropsInfo = type.GetProperties(BindingFlags.Public | BindingFlags.Instance)
        .Where(x => x.GetSetMethod(false) != null && x.GetGetMethod(false) != null)
        .Select(x => new
        {
            MemberPropName = x.Name,
            ListItemPropGetter = (Func<TModelProperty, object>)(p => x.GetValue(p, null))
        }).ToList();

    if (memPropsInfo.Count == 0)
        return HiddenForEnumerable(helper, expression);

    for (var i = 0; i < list.Count(); i++)
    {
        var listItem = list.ElementAt(i);
        foreach (var q in memPropsInfo)
        {
            sb.Append(helper.Hidden(string.Format("{0}[{1}].{2}", membername, i, q.MemberPropName), q.ListItemPropGetter(listItem)));
        }
    }

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

public static string GetMemberName<TModel, T>(this Expression<Func<TModel, T>> input)
{
    if (input == null)
        return null;

    MemberExpression memberExp = null;

    if (input.Body.NodeType == ExpressionType.MemberAccess)
        memberExp = input.Body as MemberExpression;
    else if (input.Body.NodeType == ExpressionType.Convert)
        memberExp = ((UnaryExpression)input.Body).Operand as MemberExpression;

    return memberExp != null ? memberExp.Member.Name : null;
}

//
///返回每个IEnumerable项的隐藏项及其所选属性（如果提供了MemberPropsePression）。
/// 
公共静态MvcHtmlString HiddenForEnumerable（此HtmlHelper，
表达式表达式，参数表达式[]成员属性表达式）
{
var sb=新的StringBuilder（）；
var membername=expression.GetMemberName（）；
var model=helper.ViewData.model；
var list=expression.Compile（）（模型）；
var memPropsInfo=memberPropsExpressions。选择（x=>new
{
MemberPropName=x.GetMemberName（），
ListItemPropGetter=x.Compile（）
}).ToList（）；
对于（var i=0；ix.GetSetMethod（false）！=null&&x.GetGetMethod（false）！=null）
.选择（x=>new
{
MemberPropName=x.Name，
ListItemPropGetter=（Func）（p=>x.GetValue（p，null））
}).ToList（）；
if（memPropsInfo.Count==0）
返回HiddenForEnumerable（helper，expression）；
对于（var i=0；i
递归方法怎么样
public static MvcHtmlString HiddenForEnumerable<TModel, TModelProperty>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, IEnumerable<TModelProperty>>> expression, string prefix = null)
{
    var sb = new StringBuilder();

    var membername = expression.GetMemberName();
    var model = htmlHelper.ViewData.Model;
    var list = expression.Compile()(model);

    var type = typeof(TModelProperty);
    var memPropertyInfo = type.GetProperties(BindingFlags.Public | BindingFlags.Instance)
        .Where(x => x.GetSetMethod(false) != null && x.GetGetMethod(false) != null)
        .Select(x => new
        {
            Type = x.PropertyType,
            x.Name,
            Get = (Func<TModelProperty, object>)(p => x.GetValue(p, null))
        }).ToList();

    for (var i = 0; i < list.Count(); i++)
    {
        var listItem = list.ElementAt(i);
        if (memPropertyInfo.Any())
        {
            foreach (var m in memPropertyInfo)
            {
                var inputName = $"{prefix ?? ""}{membername}[{i}].{m.Name}";
                var inputValue = m.Get(listItem);
                var genericArguments = m.Type.GetGenericArguments();

                if (genericArguments.Any() && IsEnumerableType(m.Type))
                {
                    var delegateType = typeof(Func<,>).MakeGenericType(typeof(TModel), m.Type);
                    var bodyExpression = Expression.Constant(inputValue, m.Type);
                    var paramExpression = Expression.Parameter(typeof(TModel), "model");
                    var expressionTree = Expression.Lambda(delegateType, bodyExpression, new[] { paramExpression });
                    var hiddenForEnumerableInfo = typeof(HtmlHelpers).GetMethod("HiddenForEnumerable");
                    var hiddenForEnumerable = hiddenForEnumerableInfo.MakeGenericMethod(typeof(TModel), genericArguments[0]);
                    object[] args = { htmlHelper, expressionTree, inputName };

                    sb.Append(hiddenForEnumerable.Invoke(null, args));
                }
                else
                {
                    sb.Append(htmlHelper.Hidden(inputName, inputValue));
                }
            }
        }
        else
        {
            sb.Append(htmlHelper.Hidden($"{membername}[{i}]", listItem));
        }
    }

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

private static string GetMemberName<TModel, T>(this Expression<Func<TModel, T>> input)
{
    if (input == null)
        return null;

    MemberExpression memberExp = null;

    if (input.Body.NodeType == ExpressionType.MemberAccess)
        memberExp = input.Body as MemberExpression;
    else if (input.Body.NodeType == ExpressionType.Convert)
        memberExp = ((UnaryExpression)input.Body).Operand as MemberExpression;

    return memberExp?.Member.Name;
}

private static bool IsEnumerableType(Type type)
{
    return (type.GetInterface("IEnumerable") != null);
}

输出：
<input id="Orders_0__OrderId" name="Orders[0].OrderId" type="hidden" value="1001">
<input id="Orders_0__Items_0__ItemId" name="Orders[0].Items[0].ItemId" type="hidden" value="201">
<input id="Orders_0__Items_0__Name" name="Orders[0].Items[0].Name" type="hidden" value="Something1">
<input id="Orders_0__Items_1__ItemId" name="Orders[0].Items[1].ItemId" type="hidden" value="202">
<input id="Orders_0__Items_1__Name" name="Orders[0].Items[1].Name" type="hidden" value="Something2">
<input id="Orders_1__OrderId" name="Orders[1].OrderId" type="hidden" value="1002">
<input id="Orders_1__Items_0__ItemId" name="Orders[1].Items[0].ItemId" type="hidden" value="205">
<input id="Orders_1__Items_0__Name" name="Orders[1].Items[0].Name" type="hidden" value="Something5">

对于aspnetcore也一样
using Microsoft.AspNetCore.Html;
using Microsoft.AspNetCore.Mvc.Rendering;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Reflection;
using System.Text;

namespace Proj.Helpers
{
    public static class HtmlHelpers
    {
        public static IHtmlContent HiddenForEnumerable<TModel, TModelProperty>(this IHtmlHelper<TModel> helper,
    Expression<Func<TModel, IEnumerable<TModelProperty>>> expression, params Expression<Func<TModelProperty, object>>[] memberPropsExpressions)
        {
            var hcb = new HtmlContentBuilder();

            var membername = expression.GetMemberName();
            var model = helper.ViewData.Model;
            var list = expression.Compile()(model);

            var memPropsInfo = memberPropsExpressions.Select(x => new
            {
                MemberPropName = x.GetMemberName(),
                ListItemPropGetter = x.Compile()
            }).ToList();

            for (var i = 0; i < list.Count(); i++)
            {
                var listItem = list.ElementAt(i);
                if (memPropsInfo.Any())
                {
                    foreach (var q in memPropsInfo)
                    {
                        hcb.AppendHtml(helper.Hidden(string.Format("{0}[{1}].{2}", membername, i, q.MemberPropName), q.ListItemPropGetter(listItem)));
                    }
                }
                else
                {
                    hcb.AppendHtml(helper.Hidden(string.Format("{0}[{1}]", membername, i), listItem));
                }
            }

            return hcb;
        }

        /// <summary>
        /// Returns hiddens for every IEnumerable item, with it's all public writable properties, if allPublicProps set to true.
        /// </summary>
        public static IHtmlContent HiddenForEnumerable<TModel, TModelProperty>(this IHtmlHelper<TModel> helper,
           Expression<Func<TModel, IEnumerable<TModelProperty>>> expression, bool allPublicProps)
        {
            if (!allPublicProps)
                return HiddenForEnumerable(helper, expression);

            var hcb = new HtmlContentBuilder();

            var membername = expression.GetMemberName();
            var model = helper.ViewData.Model;
            var list = expression.Compile()(model);

            var type = typeof(TModelProperty);
            var memPropsInfo = type.GetProperties(BindingFlags.Public | BindingFlags.Instance)
                .Where(x => x.GetSetMethod(false) != null && x.GetGetMethod(false) != null)
                .Select(x => new
                {
                    MemberPropName = x.Name,
                    ListItemPropGetter = (Func<TModelProperty, object>)(p => x.GetValue(p, null))
                }).ToList();

            if (memPropsInfo.Count == 0)
                return HiddenForEnumerable(helper, expression);

            for (var i = 0; i < list.Count(); i++)
            {
                var listItem = list.ElementAt(i);
                foreach (var q in memPropsInfo)
                {
                    hcb.AppendHtml(helper.Hidden(string.Format("{0}[{1}].{2}", membername, i, q.MemberPropName), q.ListItemPropGetter(listItem)));
                }
            }

            return hcb;
        }

        public static string GetMemberName<TModel, T>(this Expression<Func<TModel, T>> input)
        {
            if (input == null)
                return null;

            MemberExpression memberExp = null;

            if (input.Body.NodeType == ExpressionType.MemberAccess)
                memberExp = input.Body as MemberExpression;
            else if (input.Body.NodeType == ExpressionType.Convert)
                memberExp = ((UnaryExpression)input.Body).Operand as MemberExpression;

            return memberExp != null ? memberExp.Member.Name : null;
        }
    }
}

使用Microsoft.AspNetCore.Html；
使用Microsoft.AspNetCore.Mvc.Rendering；
使用制度；
使用System.Collections.Generic；
使用System.Linq；
使用System.Linq.Expressions；
运用系统反思；
使用系统文本；
命名空间项目帮助程序
{
公共静态类HtmlHelpers
{
公共静态IHTML内容隐藏不可计算（此IHTML帮助程序，
表达式表达式，参数表达式[]成员属性表达式）
{
var hcb=新的HtmlContentBuilder（）；
var membername=expression.GetMemberName（）；
var model=helper.ViewData.model；
var list=expression.Compile（）（模型）；
var memPropsInfo=memberPropsExpressions。选择（x=>new
{
MemberPropName=x.GetMemberName（），
@Html.HiddenForEnumerable(model => model.Orders)

<input id="Orders_0__OrderId" name="Orders[0].OrderId" type="hidden" value="1001">
<input id="Orders_0__Items_0__ItemId" name="Orders[0].Items[0].ItemId" type="hidden" value="201">
<input id="Orders_0__Items_0__Name" name="Orders[0].Items[0].Name" type="hidden" value="Something1">
<input id="Orders_0__Items_1__ItemId" name="Orders[0].Items[1].ItemId" type="hidden" value="202">
<input id="Orders_0__Items_1__Name" name="Orders[0].Items[1].Name" type="hidden" value="Something2">
<input id="Orders_1__OrderId" name="Orders[1].OrderId" type="hidden" value="1002">
<input id="Orders_1__Items_0__ItemId" name="Orders[1].Items[0].ItemId" type="hidden" value="205">
<input id="Orders_1__Items_0__Name" name="Orders[1].Items[0].Name" type="hidden" value="Something5">

using Microsoft.AspNetCore.Html;
using Microsoft.AspNetCore.Mvc.Rendering;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Linq.Expressions;
using System.Reflection;
using System.Text;

namespace Proj.Helpers
{
    public static class HtmlHelpers
    {
        public static IHtmlContent HiddenForEnumerable<TModel, TModelProperty>(this IHtmlHelper<TModel> helper,
    Expression<Func<TModel, IEnumerable<TModelProperty>>> expression, params Expression<Func<TModelProperty, object>>[] memberPropsExpressions)
        {
            var hcb = new HtmlContentBuilder();

            var membername = expression.GetMemberName();
            var model = helper.ViewData.Model;
            var list = expression.Compile()(model);

            var memPropsInfo = memberPropsExpressions.Select(x => new
            {
                MemberPropName = x.GetMemberName(),
                ListItemPropGetter = x.Compile()
            }).ToList();

            for (var i = 0; i < list.Count(); i++)
            {
                var listItem = list.ElementAt(i);
                if (memPropsInfo.Any())
                {
                    foreach (var q in memPropsInfo)
                    {
                        hcb.AppendHtml(helper.Hidden(string.Format("{0}[{1}].{2}", membername, i, q.MemberPropName), q.ListItemPropGetter(listItem)));
                    }
                }
                else
                {
                    hcb.AppendHtml(helper.Hidden(string.Format("{0}[{1}]", membername, i), listItem));
                }
            }

            return hcb;
        }

        /// <summary>
        /// Returns hiddens for every IEnumerable item, with it's all public writable properties, if allPublicProps set to true.
        /// </summary>
        public static IHtmlContent HiddenForEnumerable<TModel, TModelProperty>(this IHtmlHelper<TModel> helper,
           Expression<Func<TModel, IEnumerable<TModelProperty>>> expression, bool allPublicProps)
        {
            if (!allPublicProps)
                return HiddenForEnumerable(helper, expression);

            var hcb = new HtmlContentBuilder();

            var membername = expression.GetMemberName();
            var model = helper.ViewData.Model;
            var list = expression.Compile()(model);

            var type = typeof(TModelProperty);
            var memPropsInfo = type.GetProperties(BindingFlags.Public | BindingFlags.Instance)
                .Where(x => x.GetSetMethod(false) != null && x.GetGetMethod(false) != null)
                .Select(x => new
                {
                    MemberPropName = x.Name,
                    ListItemPropGetter = (Func<TModelProperty, object>)(p => x.GetValue(p, null))
                }).ToList();

            if (memPropsInfo.Count == 0)
                return HiddenForEnumerable(helper, expression);

            for (var i = 0; i < list.Count(); i++)
            {
                var listItem = list.ElementAt(i);
                foreach (var q in memPropsInfo)
                {
                    hcb.AppendHtml(helper.Hidden(string.Format("{0}[{1}].{2}", membername, i, q.MemberPropName), q.ListItemPropGetter(listItem)));
                }
            }

            return hcb;
        }

        public static string GetMemberName<TModel, T>(this Expression<Func<TModel, T>> input)
        {
            if (input == null)
                return null;

            MemberExpression memberExp = null;

            if (input.Body.NodeType == ExpressionType.MemberAccess)
                memberExp = input.Body as MemberExpression;
            else if (input.Body.NodeType == ExpressionType.Convert)
                memberExp = ((UnaryExpression)input.Body).Operand as MemberExpression;

            return memberExp != null ? memberExp.Member.Name : null;
        }
    }
}