How one can use guard clauses in C#

• You need to use guard clauses in your strategies to forestall runtime exceptions by dealing with null reference exceptions.
• You need to use guard clauses to validate enter information and implement information integrity by solely processing legitimate inputs.
• You need to use guard clauses to outline preconditions to your strategies and properties, enhancing the readability and maintainability of your code.

We’ll look at every of those features of guard clauses utilizing code examples within the sections that observe.

Use a guard clause to keep away from null reference exceptions in C#

Null reference exceptions are sometimes encountered in functions if you use an object reference that has not been initialized. On this part, we are going to look at how we are able to use a guard clause to forestall such exceptions from being thrown at runtime. The next code snippet exhibits how one can examine if the parameter of a technique is null and throw an ArgumentNullException, stopping a null reference exception from being thrown at runtime and permitting the tactic to finish gracefully.

public void CheckIfNull(object obj)
{
    if (obj is null)
    {
        throw new ArgumentNullException(nameof(obj), "Methodology parameter can't be null.");
    }
    //Different code
}

Use a guard clause to implement enter validation guidelines in C#

Enter validation allows you to preserve information integrity by implementing validation guidelines and constraints in your software. You may implement guard clauses in your software’s supply code to permit solely legitimate information to be processed by your software.

The next code instance exhibits how you need to use a guard clause in C# to forestall invalid enter. Word how an exception is thrown if the enter string is null or empty.

public void CheckIfNullOrEmpty(string str)
{
    if(!string.IsNullOrEmpty(str))
    {
        throw new ArgumentException("Invalid information: The string handed within the methodology argument can't be empty or null");
    }
    //Different code
}

Use a guard clause to reinforce code readability and maintainability in C#

Guard clauses provide help to write maintainable and readable code by centralizing your software’s validation guidelines. They supply a chic solution to stop sudden conduct in your software’s code, making it constant, organized, and straightforward to take care of.

Allow us to perceive this with a code instance. Within the console software venture we created earlier, create a brand new class named Creator and enter the next code.

class Creator
{
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string Handle { get; set; }
    public string E-mail { get; set; }
}

The next code snippet illustrates how one can benefit from the constructor of the Creator class to validate enter.

 public Creator(string firstName, string lastName, string deal with, string e-mail)
 {
     if (string.IsNullOrEmpty(firstName))
     {
         throw new ArgumentException("First title can't be null or empty", nameof(firstName));
     }
     if (string.IsNullOrEmpty(lastName))
     {
         throw new ArgumentException("Final title can't be null or empty", nameof(lastName));
     }
     if (string.IsNullOrEmpty(deal with))
     {
         throw new ArgumentException("Handle can't be null or empty", nameof(deal with));
     }
     if (string.IsNullOrEmpty(e-mail))
     {
         throw new ArgumentException("E-mail can't be null or empty", nameof(e-mail));
     }
 }

As you may see, the previous code snippet is kind of verbose. We will make it way more concise and readable by utilizing guard clauses. Word that the next code can exchange all the if statements used within the constructor of the Creator class above.