Returns a copy of this String object converted to lowercase using the casing rules of the invariant culture.
Assembly: mscorlib (in mscorlib.dll)
The invariant culture represents a culture that is culture-insensitive. It is associated with the English language but not with a specific country or region. For more information, see the CultureInfo.InvariantCulture property.
If your application depends on the case of a string changing in a predictable way that is unaffected by the current culture, use the method. The method is equivalent to ToLower(CultureInfo.InvariantCulture). The method is recommended when a collection of strings must appear in a predictable order in a user interface control.
This method does not modify the value of the current instance. Instead, it returns a new string in which all characters in the current instance are converted to lowercase.
If you need the lowercase or uppercase version of an operating system identifier, such as a file name, named pipe, or registry key, use the or ToUpperInvariant methods.
The following example defines a string array that contains a single word in a number of languages. The method is used to populate the elements of a parallel array with the case-insensitive version of each word. The Array.Sort(TKey, TValue)(TKey, TValue, IComparer(TKey)) method is used to sort the case-sensitive array based on the order of elements in the lowercase array to ensure that elements appear in the same order regardless of language.