# Ensure

`Ensure` static class with its methods provides functionality for determining if variable's value meets specified conditions and throw exception if it's not.

## NotNull

Throws `ArgumentNullException` when value of specified variable is null:

```csharp
object myValue = null;
Ensure.NotNull(myValue, nameof(myValue)); // --> throws ArgumentNullException
myValue = "123456";
Ensure.NotNull(myValue, nameof(myValue)); // --> does nothing
```

## NotEmpty

Throws ArgumentNullException when value of specified string variable is null or empty or consists only of white-space characters:

```csharp
string? myValue = null;
Ensure.NotNull(myValue, nameof(myValue)); // --> throws ArgumentNullException
myValue = "        ";
Ensure.NotNull(myValue, nameof(myValue)); // --> throws ArgumentNullException
myValue = "abcdef";
Ensure.NotNull(myValue, nameof(myValue)); // --> does nothing
```

## Other methods

Other methods to check variables are listed below:

* InRange
* GreaterThan
* LessThan

Each of them got three different versions for `string`, `DateTime` and `IComparable` values.


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