public class PostTypeCategoryVM
{
    public int PostId { get; set; }
    public int? PostParentId { get; set; }
    public Post post { get; set; }
    public int PostTypeId { get; set; }
    //[Required]
    public string PostType { get; set; }
    //[Required]
    public DateTime PublishDate { get; set; }
    //[Required]
    public DateTime UnPublishDate { get; set; }
    [Required]
    public List<string> SelectedCategories { get; set; }
    [Required]
    public int selectedStatus { get; set; }
    public List<PostStatusVM> PostStatus { get; set; }
    [Required]
    public List<PostTypeVM> PostCategories { get; set; }
    //[Required]

    public List<PostDetailVM> PostDetailVM { get; set; }

public class PostDetailVM
{

    [PostTitle]
    public string Title { get; set; }
    [Required]
    public string Content { get; set; }
    public int LangId { get; set; }
    [Required]
    public string Slug {get;set;}

public class PostTitleAttribute : ValidationAttribute
{



    protected override ValidationResult IsValid(object value,
                  ValidationContext validationContext)
    {

        var lang = (PostDetailVM)validationContext.ObjectInstance;

        if (lang.LangId==1 && string.IsNullOrEmpty(lang.Title))
        {
            return new ValidationResult("English Title is required");

        }
        if (lang.LangId == 2 && string.IsNullOrEmpty(lang.Title))
        {
            return new ValidationResult("Darri Title is required");

        }
        return ValidationResult.Success;

    }


    }

@model SepiaCMS.Models.PostTypeCategoryVM
 <div>@Html.ValidationSummary("Please correct below Errors")</div>
    <div class="container">
        <div class="col-md-12">
            <div id="appendView">
            </div>
        </div>

        <div class="col-md-6">
            <ul class="nav nav-tabs" id="tabs">

                @foreach (var item in (IEnumerable<SepiaCMS.Models.lang>)ViewBag.Languages)
                {
                    if (i == 0)
                    {

                        <li class="nav active"><a href="#@item.langid" data-toggle="tab"><label><input type="checkbox" checked="checked" name="IsCheck" />&nbsp;@item.langname</label></a></li>
                    }
                    else
                    {
                        <li class="nav"><a href="#@item.langid" data-toggle="tab"><input type="checkbox" name="IsCheck" checked="checked" />&nbsp;@item.langname</a></li>
                    }
                    { i = i + 1; }
                }
            </ul>

            <!-- Tab panes -->

            <div class="tab-content">
                @{int kk = 0; }
                @foreach (var item in (IEnumerable<SepiaCMS.Models.lang>)ViewBag.Languages)
                {
                    if (k == 0)
                    {

                <div class="tab-pane fade in active" id="@item.langid">

                    <span>Post Title</span><br />

                    @Html.TextBoxFor(m => m.PostDetailVM[kk].Title, new { @id = "lang-" + item.langid, @class = "txtfortitle" })<br />
                    @*@Html.ValidationMessageFor(m => m.PostDetailVM[kk].Title, "*", new { @class = "text-danger" })*@
                    <span>Description</span><br />
                    @Html.TextAreaFor(m => m.PostDetailVM[kk].Content, 20, 10, new { @class = "txtForPost" })
                    @*@Html.ValidationMessageFor(m => m.PostDetailVM[kk].Content, "", nejjw { @class = "text-danger" })*@
                    @Html.LabelFor(m => m.PostDetailVM[kk].Slug, "Enter Slug")
                    @Html.TextBoxFor(m => m.PostDetailVM[kk].Slug, new { @class = "txtslug" })
                    @*@Html.ValidationMessageFor(m => m.PostDetailVM[kk].Slug, "", new { @class = "text-danger" })*@
                    <input type="hidden" name="PostDetailVM[@kk].LangId" value="@item.langid" />
                    @*<input type="button" value="Done" class="btn btn-success" id="btnSubmit" />
    <a href="#" class="btn btn-default" data-dismiss="modal">Cancel</a>*@
                    <div style="text-align:center;display:none" id="loaderDiv">
                        <img src="~/Content/InternetSlowdown_Day.gif" width="150" />
                    </div>
                </div>

                    }
                    else
                    {
                        <div class="tab-pane fade" id="@item.langid">
                            <span>Post Title</span><br />
                            @Html.TextBoxFor(m => m.PostDetailVM[kk].Title, new { @id = "lang-" + item.langid, @class = "txtfortitle" })<br />
                            @*@Html.ValidationMessageFor(m => m.PostDetailVM[kk].Title, "", new { @class = "text-danger" })*@
                            <span>Description</span><br />
                            @Html.TextAreaFor(m => m.PostDetailVM[kk].Content, 20, 10, new { @class = "txtForPost" })
                            @*@Html.ValidationMessageFor(m => m.PostDetailVM[kk].Content, "", new { @class = "text-danger" })*@
                            @Html.LabelFor(m => m.PostDetailVM[kk].Slug, "Enter Slug")
                            @Html.TextBoxFor(m => m.PostDetailVM[kk].Slug, new { @class = "txtslug" })
                            @*@Html.ValidationMessageFor(m => m.PostDetailVM[kk].Slug, "", new { @class = "text-danger" })*@
                            <input type="hidden" name="PostDetailVM[@kk].LangId" value="@item.langid" />
                            @*<input type="button" value="Done" class="btn btn-success" id="btnSubmit" />
                                <a href="#" class="btn btn-default" data-dismiss="modal">Cancel</a>*@
                            <div style="text-align:center;display:none" id="loaderDiv">
                                <img src="~/Content/InternetSlowdown_Day.gif" width="150" />
                            </div>
                        </div>
                    }
                    { k = k + 1; }
                    { kk = kk + 1; }
                }