/// <summary>
/// Reports the zero-based index and length of the first occurrence of the specified substring in the source string.
/// </summary>
/// <param name="source">The source string in which to search.</param>
/// <param name="substring">The substring to seek.</param>
/// <param name="searchIndex">The zero-based starting character position in <paramref name="source"/> to search from.</param>
/// <param name="comparisonType">One of the enumeration values that specifies the rules for the search.</param>
/// <param name="matchIndex">
/// When this method returns, contains the zero-based starting character position of the match, if found;
/// or -1 if no match is found.
/// If <paramref name="substring"/> is the empty string (<c>""</c>), the value will be <paramref name="searchIndex"/>.
/// </param>
/// <param name="matchLength">
/// When this method returns, contains the length (in characters) of the match, if found;
/// or -1 if no match is found.
/// If <paramref name="substring"/> is the empty string (<c>""</c>), the value will be 0.
/// </param>
/// <remarks>
/// Refer to the remarks on the <see cref="Find(string, string, int, int, StringComparison, out int, out int)"/> overload.
/// </remarks>
public static void Find(this string source, string substring, int searchIndex, StringComparison comparisonType, out int matchIndex, out int matchLength)
{
ArgumentValidate.NotNull(source, nameof(source));
ArgumentValidate.NotNull(substring, nameof(substring));
ArgumentValidate.StringIndex(source, nameof(source), searchIndex, nameof(searchIndex));
ArgumentValidate.EnumDefined(comparisonType, nameof(comparisonType));
FindInner(source, substring, searchIndex, source.Length - searchIndex, comparisonType, out matchIndex, out matchLength);
}
/// <summary>
/// Reports the zero-based index and length of the first occurrence of the specified substring in the source string.
/// </summary>
/// <param name="source">The source string in which to search.</param>
/// <param name="searchValue">The substring to seek.</param>
/// <param name="searchIndex">The zero-based starting character position in <paramref name="source"/> to search from.</param>
/// <param name="comparisonType">One of the enumeration values that specifies the rules for the search.</param>
/// <param name="matchIndex">
/// When this method returns, contains the zero-based starting character position of the match, if found;
/// or -1 if no match is found.
/// If <paramref name="searchValue"/> is the empty string (<c>""</c>),
/// the value will be <paramref name="searchIndex"/>.
/// </param>
/// <param name="matchLength">
/// When this method returns, contains the length (in characters) of the match, if found;
/// or -1 if no match is found.
/// If <paramref name="searchValue"/> is the empty string (<c>""</c>), the value will be 0.
/// </param>
/// <returns>
/// <see langword="true"/> if a match for <paramref name="searchValue"/> is found in the source string;
/// otherwise, <see langword="false"/>.
/// </returns>
/// <remarks>
/// Refer to the remarks on the
/// <see cref="Find(string, string, int, int, StringComparison, out int, out int)"/> overload.
/// </remarks>
public static bool Find(this string source, string searchValue, int searchIndex, StringComparison comparisonType, out int matchIndex, out int matchLength)
{
ArgumentValidate.NotNull(source, nameof(source));
ArgumentValidate.NotNull(searchValue, nameof(searchValue));
ArgumentValidate.StringIndex(source, nameof(source), searchIndex, nameof(searchIndex));
ArgumentValidate.EnumDefined(comparisonType, nameof(comparisonType));
return(FindInner(source, searchValue, searchIndex, source.Length - searchIndex, comparisonType, out matchIndex, out matchLength));
}
private static void StringIndexFail <TException>(
string str, int idx,
bool strFail = false, bool idxFail = false)
where TException : ArgumentException
{
var exception = ExceptionAssert.Throws <TException>(() =>
ArgumentValidate.StringIndex(str, nameof(str), idx, nameof(idx)));
string failParamName =
strFail ? nameof(str) :
idxFail?nameof(idx) : null;
Assert.AreEqual(failParamName, exception.ParamName);
}
public void StringIndex()
{
string str;
int idx;
ArgumentValidate.StringIndex("", nameof(str), 0, nameof(idx));
ArgumentValidate.StringIndex("abc", nameof(str), 0, nameof(idx));
ArgumentValidate.StringIndex("abc", nameof(str), 1, nameof(idx));
ArgumentValidate.StringIndex("abc", nameof(str), 2, nameof(idx));
ArgumentValidate.StringIndex("abc", nameof(str), 3, nameof(idx));
StringIndexFail <ArgumentNullException>(null, 0, strFail: true);
StringIndexFail <ArgumentOutOfRangeException>("", 1, idxFail: true);
StringIndexFail <ArgumentOutOfRangeException>("abc", 4, idxFail: true);
}