Error when trying to get value from an object: Object reference not set [duplicate]

This question already has an answer here:

• What is a NullReferenceException and how do I fix it? 18 answers

The application I'm working on has a piece of code which fails occasionally when object's property's value is null.

I need to check for the value before using this code:

    foreach(PropertyInfo pInfo in this.GetType().GetProperties()) 
    {
        int index = pInfo.Name.IndexOfAny(new char[] {'2'});

        if( index > -1 && pInfo.PropertyType.ToString() != "System.Boolean" && pInfo.Name != "Bank2AccountType"
            && ! pInfo.PropertyType.IsEnum )
        {
            // Get the value of the current property
            string propertyValue = pInfo.GetValue(this, null).ToString();

            if( propertyValue != string.Empty )
            {
                // There is a value in the current property, the bank 2 is not empty
                isEmpty = false;

                // There is no need to do further checks, break out of the loop and return
                break;
            }
        }

        propertyIndex++;
    }

This is where it fails:

string propertyValue = pInfo.GetValue(this, null).ToString();

I assume, that this is the object which has 'pInfo' property.

I need to check for null before assigning it to "propertyValue" variable

What is the right way to do so?