/// <summary>
/// Checks whether the registry number is valid.
/// </summary>
/// <param name="casNumber">the CAS number to validate</param>
/// <returns>true if a valid CAS number, false otherwise</returns>
// @cdk.keyword CAS number
// @cdk.keyword validation
public static bool IsValid(string casNumber)
{
bool overall = true;
// check format
var matcher = pattern.Match(casNumber);
overall = overall && matcher.Success;
if (matcher.Success)
{
// check number
string part1 = matcher.Groups[1].Value;
string part2 = matcher.Groups[2].Value;
string part3 = matcher.Groups[3].Value;
int part1value = int.Parse(part1, NumberFormatInfo.InvariantInfo);
if (part1value < 50)
{
overall = false;
// CAS numbers start at 50-00-0
}
else
{
int digit = CASNumber.CalculateCheckDigit(part1, part2);
overall = overall && (digit == int.Parse(part3, NumberFormatInfo.InvariantInfo));
}
}
return(overall);
}
public void TestWrongHyphenPositions()
{
// invalid format due to invalid hyphen positions
Assert.IsFalse(CASNumber.IsValid("3-21-40"));
Assert.IsFalse(CASNumber.IsValid("3-210-4"));
Assert.IsFalse(CASNumber.IsValid("03-1-4"));
Assert.IsFalse(CASNumber.IsValid("03-21-"));
}
public void TestInvalidCharacters()
{
// invalid characters
Assert.IsFalse(CASNumber.IsValid("a-21-4"));
Assert.IsFalse(CASNumber.IsValid("3-a1-4"));
Assert.IsFalse(CASNumber.IsValid("3-2a-4"));
Assert.IsFalse(CASNumber.IsValid("3-21-a"));
Assert.IsFalse(CASNumber.IsValid("d-cb-a"));
}
public void TestValidNumbers()
{
// valid cas numbers
Assert.IsTrue(CASNumber.IsValid("50-00-0")); // formaldehyde
Assert.IsTrue(CASNumber.IsValid("548-00-5"));
Assert.IsTrue(CASNumber.IsValid("2622-26-6"));
Assert.IsTrue(CASNumber.IsValid("15299-99-7"));
Assert.IsTrue(CASNumber.IsValid("673434-32-7"));
}
public void TestInvalidCheckDigits()
{
// invalid R value
Assert.IsFalse(CASNumber.IsValid("50-00-1"));
Assert.IsFalse(CASNumber.IsValid("50-00-2"));
Assert.IsFalse(CASNumber.IsValid("50-00-3"));
Assert.IsFalse(CASNumber.IsValid("50-00-4"));
Assert.IsFalse(CASNumber.IsValid("50-00-5"));
Assert.IsFalse(CASNumber.IsValid("50-00-6"));
Assert.IsFalse(CASNumber.IsValid("50-00-7"));
Assert.IsFalse(CASNumber.IsValid("50-00-8"));
Assert.IsFalse(CASNumber.IsValid("50-00-9"));
}
public void TestCharacterSet()
{
// invalid value even with the '0' unicode character '\u0030'
Assert.IsFalse(CASNumber.IsValid("\u0030-21-4"));
}
public void TestSanity()
{
// completely stupid value
Assert.IsFalse(CASNumber.IsValid("0&z003-!0>/-0a"));
}
public void TestLargerThanFirst()
{
// valid format, but wrong number, the first is 50-00-0
Assert.IsFalse(CASNumber.IsValid("3-21-4"));
}
