How to use Object.ReferenceEquals(null, myObjVar) to solve error object reference not set to an instance of an object ?

Question

I work on csharp i get error object reference not set to an instance of an object

so how to use Object.ReferenceEquals(null, myObjVar) to solve error

code give me error

 var Data = result.items.Select(e => new { PartID = e.create._id, IsUpdated = e.create.error != null && e.create.error.reason !=null && !e.create.error.reason.Contains("document already exists") ? 0 : 1, ErrorStatus = e.create.error == null  | (e.create.error.reason!=null && e.create.error.reason.Contains("document already exists")) ? null : e.create.error.reason }).ToList();  

ElasticPartialUpdat.Create.error.get returned null.

How to use this lines below to solve error

if (Object.ReferenceEquals(null, myObjVar))  {    .......  }   

Answer 1

Here is an example which should help.

public class MonthData : IEquatable<MonthData>  
{  
	public string Month { get; set; }  
	public int Index { get; set; }  
  
	public override string ToString()  
	{  
		return $"{{ Month = {Month}, Index = {Index} }}";  
	}  
  
	public bool Equals(MonthData other)  
	{  
		if (ReferenceEquals(null, other)) return false;  
		if (ReferenceEquals(this, other)) return true;  
		return Month == other.Month && Index == other.Index;  
	}  
  
	public override bool Equals(object obj)  
	{  
		if (ReferenceEquals(null, obj)) return false;  
		if (ReferenceEquals(this, obj)) return true;  
		if (obj.GetType() != this.GetType()) return false;  
		return Equals((MonthData) obj);  
	}  
  
	public override int GetHashCode()  
	{  
		return HashCode.Combine(Month, Index);  
	}  
}  

It's always good to read the docs