ASP.NET MVC Web Application - Facing Null Pointer Exception

Question

I am getting this exception whenever I try to call this redirect link on Employee data Image. Any help which could solve this problem is much appreciated.

My Work:

Employee View empRecords:

@using PagedList.Mvc;
@using PagedList;
@model IPagedList
@{
    HttpCookie cookie = Request.Cookies["Detalis"];
    Layout = null;
}



    
    EmpRecords
    


    
        @Html.ActionLink("Create New", "Create")
    
    
        @{
            String img64 = (string)Session["userImage"];
            String img64Url = string.Format("data:image/" +
           (string)Session["userImageType"] + ";base64,{0}", img64);
            //imagetype can be e.g. gif, jpeg, png etc.
        }
        
        

        @Html.ActionLink("Click to Logout", "Logout", "User")
    
    

    

        @Html.Partial("_EmployeeInfo", Model)
    
    

    
        
            
                @Html.ActionLink("User Last Login:", cookie["Lastlogin"])
            
            
                @if (cookie != null)
                {
                    @cookie["Lastlogin"];
                }

Partial Layout View _EmployeeInfo:

@using PagedList.Mvc;
@using PagedList;
@model IPagedList

    @if (Model.Count() == 0)
    {
        
    }
    else
    {
        foreach (var item in Model)
        {
            using (Html.BeginForm("Delete", "Employee", new
            {
                id =
           item.EmployeeID
            }))
            {
                
            }
        }
    }

    
        
            @Html.DisplayNameFor(model => model.First().EmployeeID)
        
        
            @Html.DisplayNameFor(model => model.First().FirstName)
        
        
            @Html.DisplayNameFor(model => model.First().ImageURL)
        
        
            Image
        
    

            
                No records match search criteria
            
        

                    
                        @Html.DisplayFor(modelItem => item.EmployeeID)
                    
                    
                        @Html.DisplayFor(modelItem =>
                       item.FirstName)
                    
                    
                        @Html.DisplayFor(modelItem => item.ImageURL)
                    
                    
                        @if (!string.IsNullOrEmpty(item.ImageURL))
                         {
                           
                              @*@Url.Content convert the relative path into application absolute path*@
                              
                           
                         }
                         else
                         {
                            No Image Found!
                         }
                    
                
@Html.PagedListPager(Model, page => Url.Action("empRecords", new { page,
SearchBy = Request.QueryString["SearchBy"], SearchTerm =
Request.QueryString["SearchTerm"], sortBy =
Request.QueryString["sortBy"] }), new PagedListRenderOptions() {
Display = PagedListDisplayMode.IfNeeded,
DisplayPageCountAndCurrentLocation = true })

so, the main problem is that whenever I tried to call this redirect link I faced this error:

Code:

@if (!string.IsNullOrEmpty(item.ImageURL))
{
    
        @*@Url.Content convert the relative path into application absolute path*@
        
    
}

Error Message:

Employee Controller functions used for following task:

public ActionResult empRecords(string SearchBy, string SearchTerm, int? page, string sortBy)
{
    //In case of Invalid user redirect to login
    if (Session["login"] == null)
    {
        return RedirectToAction("Login", "User");
    }
    EmployeeEntity entity = new EmployeeEntity();
    List list = entity.GetList(SearchBy,SearchTerm, sortBy);
    HttpCookie cookie = Request.Cookies["Detalis"];
    if (cookie != null)
    {
        string color = cookie["Lastlogin"];
    }

    return View(list.ToPagedList(page ?? 1, 5));
}

public ActionResult Details(long id)
{
    //In case of Invalid user redirect to login
    if (Session["login"] == null)
    {
        return RedirectToAction("Login", "User");
    }
    EmployeeEntity entity = new EmployeeEntity();
    Employee employee = entity.GetSingleEmployee(id);
    HttpCookie cookie = Request.Cookies["Detalis"];
    if (cookie != null)
    {
        string color = cookie["Lastlogin"];
    }
    return View(employee);

}

Employee View Details:

@model My_Work.Models.Employee
@{
    Layout = null;
    HttpCookie cookie = Request.Cookies["Detalis"];
}



    
    Employee Detail
    


    
        Employee Detail
        
        
            
                @Html.DisplayNameFor(model => model.EmployeeID)
            

            
                @Html.DisplayFor(model => model.EmployeeID)
            
            
                @Html.DisplayNameFor(model => model.FirstName)
            

            
                @Html.DisplayFor(model => model.FirstName)
            

            
                @Html.DisplayNameFor(model => model.LastName)
            

            
                @Html.DisplayFor(model => model.LastName)
            
            
                @{
                    String img64 = (string)Session["userImage"];
                    String img64Url = string.Format("data:image/" +
                   (string)Session["userImageType"] + ";base64,{0}", img64);
                    //imagetype can be e.g. gif, jpeg, png etc.
                }
                
            
        
    
    
        @Html.ActionLink("Edit", "Edit", new { id = Model.EmployeeID
       }) |
        @Html.ActionLink("Back to List", "empRecords")

Yong Shun · Accepted Answer

ISSUE

You get the above error as id is the mandatory parameter in Details function (action) in Employee controller.


    @*@Url.Content convert the relative path into application absolute path*@

SOLUTION

You have to make sure that id must be included in the URL for redirecting to Employee/Details.

The URL should be as below:

/Employee/Details/{id}

SOLUTION 1:


    @*@Url.Content convert the relative path into application absolute path*@

SOLUTION 2:


    @*@Url.Content convert the relative path into application absolute path*@

ASP.NET MVC Web Application - Facing Null Pointer Exception

Answers (2)

ISSUE

SOLUTION

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