To get a trial key
fill out the form below
Team license
Enterprise license
** By clicking this button you agree to our Privacy Policy statement

Request our prices
New License
License Renewal
--Select currency--
USD
EUR
RUB
* By clicking this button you agree to our Privacy Policy statement

Free PVS-Studio license for Microsoft MVP specialists
** By clicking this button you agree to our Privacy Policy statement

To get the licence for your open-source project, please fill out this form
** By clicking this button you agree to our Privacy Policy statement

I am interested to try it on the platforms:
** By clicking this button you agree to our Privacy Policy statement

Message submitted.

Your message has been sent. We will email you at


If you haven't received our response, please do the following:
check your Spam/Junk folder and click the "Not Spam" button for our message.
This way, you won't miss messages from our team in the future.

>
>
>
V3179. Calling element access method fo…
Analyzer diagnostics
General Analysis (C++)
General Analysis (C#)
General Analysis (Java)
Diagnosis of micro-optimizations (C++)
Diagnosis of 64-bit errors (Viva64, C++)
Customer specific requests (C++)
MISRA errors
AUTOSAR errors
OWASP errors (C#)
Problems related to code analyzer
Additional information
Contents

V3179. Calling element access method for potentially empty collection may result in exception.

Sep 07 2022

The analyzer detected that a potentially empty collection has a method call that throws an exception if there are no elements in the collection.

To better understand this, let's look at the following example:

public static bool ComparisonWithFirst(List<string> list,
                                       string strForComparison)
{
  string itemForComparison = null;

  if (list != null && !list.Any())
  {
    itemForComparison = list.First();
  }
  ....
}

An attempt to access the first element from the collection results in 'InvalidOperationException'. Inside the then branch the collection is empty, because the 'list' has been checked for containing no elements.

Let's look at the fixed version:

public static bool ComparisonWithFirst(List<string> list,
                                       string strForComparison)
{
  string itemForComparison = null;

  if (list != null && list.Any())
  {
    itemForComparison = list.First();
  }
  ....
}

If we pass an empty collection to the method that doesn't expect this, we can get a similar error.

public static void ProcessList(List<string> list)
{
  if (list.Any())
    return;

  CompareFirstWithAll(list);
}

public static void CompareFirstWithAll(List<string> list)
{
  string itemForComparison = list.First();
  ....
}

The 'ProcessList' method contains a typo, so the empty 'list' collection is passed to the 'CompareFirstWithAll' method. The 'CompareFirstWithAll' method does not expect to receive an empty collection.

Let's look at the fixed version:

public static void ProcessList(List<string> list)
{
  if (!list.Any())
    return;

  CompareFirstWithAll(list);
}
Unicorn with delicious cookie
Our website uses cookies to enhance your browsing experience. Would you like to learn more?
Accept