I am working on an ASP.NET MVC 4 application. I use EF 5 with code first and in one of my entities I have :
public string ImageName { get; set; }
public string ImageGUIDName { get; set; }
those two properties which are part of my entity. Since I may not have image uploaded these values can be null but when I render the view passing the model with ImageName and ImageGUIDName coming as null from the database I get this :
Exception Details: System.ArgumentNullException: Value cannot be null.
The basic idea is to provide different text for the user based on the fact if there is picture or not:
@if (Model.ImageName != null)
{
<label for="Image">Change picture</label>
}
else
{
<label for="Image">Add picture</label>
}
So when the above code got me that error I tried with string.IsNullOrEmpty(Model.ImageName) and also Model.ImageName.DefaultIfEmpty() != null but I got the exact same error. It seems that I can not just set y entity property as nullable:
public string? ImageName { get; set; } //Not working as it seems
So how can I deal with this?
This question is related to
c#
entity-framework
asp.net-mvc-4
razor
Try this first, you may be passing a Null Model:
@if (Model != null && !String.IsNullOrEmpty(Model.ImageName))
{
<label for="Image">Change picture</label>
}
else
{
<label for="Image">Add picture</label>
}
Otherise, you can make it even neater with some ternary fun! - but that will still error if your model is Null.
<label for="Image">@(String.IsNullOrEmpty(Model.ImageName) ? "Add" : "Change") picture</label>
Source: Stackoverflow.com