WhiteSpace Constraint

WhiteSpaceConstraint tests that a string is null, empty, or contains only whitespace characters. It is equivalent to string.IsNullOrWhiteSpace().

Note

This constraint was added in NUnit 4.2.

Usage

Is.WhiteSpace
Is.Not.WhiteSpace

Examples

[Test]
public void WhiteSpaceConstraint_Examples()
{
    Assert.That("", Is.WhiteSpace);           // Empty string
    Assert.That(" ", Is.WhiteSpace);          // Space
    Assert.That("  \t\n", Is.WhiteSpace);     // Mixed whitespace
    Assert.That(null, Is.WhiteSpace);         // Null

    Assert.That("Hello", Is.Not.WhiteSpace);
    Assert.That(" Hello ", Is.Not.WhiteSpace);  // Has non-whitespace content
}

Notes

  1. Whitespace characters are defined by the Unicode standard as interpreted by Char.IsWhiteSpace().
  2. Unlike Is.Empty, Is.WhiteSpace also returns true for null values.
  3. Common whitespace characters include: space ( ), tab (\t), newline (\n), carriage return (\r).

See Also