_IWebHostEnvironment.WebRootPath threw an exception 'System.Null Reference "

Question

I uploading files in asp.net core mvc i create folder for images in wwwroot with the name of photo and write a program in controller in which gives error of null _IWebHostEnvironment.WebRootPath can anybody help me.

namespace eHouse.Controllers {

public class AddPropertyRentController1 : Controller
{

    Rentdb DB =new Rentdb();
    IWebHostEnvironment _IWebHostEnvironment;
    public IActionResult aprent()
    {
        return View();
    }
    [HttpPost]
    public IActionResult aprent([Bind] RentModel ar)
    {


        if (ar.imge1 != null)
        {
            string folder = "image/";
            folder += ar.imge1.FileName + Guid.NewGuid().ToString();
            ar.pic1 = folder;

            string serverFolder = Path.Combine(_IWebHostEnvironment.WebRootPath, folder);
            ar.imge1.CopyToAsync(new FileStream(serverFolder, FileMode.Create));
            
        }

You don't assign a value to `_IWebHostEnvironment` so it will, of course, be the default value for a reference type: `null`. — ProgrammingLlama, Oct 24 '22 at 09:47

Qing Guo · Accepted Answer · 2022-10-24T09:58:24.630

1

I have test your code, and I meet the same error as you. When I add parameter to AddPropertyRentController1 to set the value for the _IWebHostEnvironment then the error disappear.

Try to add below code:

public class AddPropertyRentController1 : Controller
{
         private IWebHostEnvironment _IWebHostEnvironment;
         public AddPropertyRentController1(IWebHostEnvironment IWebHostEnvironment)
                {
                   _IWebHostEnvironment = IWebHostEnvironment;
                }
}

edited Oct 24 '22 at 09:58

answered Oct 24 '22 at 09:32

Qing Guo

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Simply adding code with no explanation does not make a good answer. – DavidG Oct 24 '22 at 09:47
Ok, I update my answer , I will notice next time. Thanks. – Qing Guo Oct 24 '22 at 10:00
Thanks its use full for me but now i have some issue in model.state in which validation state of pic is invalid and i put no validation kindly guide me if (ModelState.IsValid) { string res = DB.Saverecord(ar); string pics = DB.imagedb(ar); TempData["msg"] = res; } – Creative Things Oct 24 '22 at 10:38
@CreativeThings If my answer help you resolve your 'System.Null Reference ", could you please accept as answer? Refer to:[How to access an answer](https://meta.stackexchange.com/questions/5234/how-does-accepting-an-answer-work/5235#5235) Thanks. The some issue in model.state , you can create a new post to describe the problem clearly so that we can help you. – Qing Guo Oct 25 '22 at 01:53

_IWebHostEnvironment.WebRootPath threw an exception 'System.Null Reference "

1 Answers1