IndicesOf
Gets all the indexes in which a certain substring appears within the string.
Source
public static IEnumerable<int> IndicesOf(this string searchIn, string searchFor)
{
if (string.IsNullOrEmpty(searchFor)) yield break;
int lastLoc = searchIn.IndexOf(searchFor);
while (lastLoc != -1)
{
yield return lastLoc;
lastLoc = searchIn.IndexOf(searchFor, startIndex: lastLoc + 1);
}
}Example
[Test]
public void TestStringIndicesOf()
{
CollectionAssert.AreEquivalent("babbab".IndicesOf("b"), new[] { 0,2,3,5});
CollectionAssert.AreEquivalent("babbab".IndicesOf("ba"), new[] { 0, 3 });
CollectionAssert.AreEquivalent("babbab".IndicesOf("cgesahghts"), Enumerable.Empty<int>());
CollectionAssert.AreEquivalent("babbab".IndicesOf(string.Empty), Enumerable.Empty<int>());
}