Join() [4/7]

static string System.String.Join ( string? separator, IEnumerable< string?> values )

inlinestatic

Definition at line 2035 of file String.cs.

    {
        if (values is List<string> list)
        {
            return JoinCore(separator.AsSpan(), CollectionsMarshal.AsSpan(list));
        }
        if (values is string[] array)
        {
            return JoinCore(separator.AsSpan(), new ReadOnlySpan<string>(array));
        }
        if (values == null)
        {
            ThrowHelper.ThrowArgumentNullException(ExceptionArgument.values);
        }
        using IEnumerator<string> enumerator = values.GetEnumerator();
        if (!enumerator.MoveNext())
        {
            return Empty;
        }
        string current = enumerator.Current;
        if (!enumerator.MoveNext())
        {
            return current ?? Empty;
        }
        Span<char> initialBuffer = stackalloc char[256];
        ValueStringBuilder valueStringBuilder = new ValueStringBuilder(initialBuffer);
        valueStringBuilder.Append(current);
        do
        {
            valueStringBuilder.Append(separator);
            valueStringBuilder.Append(enumerator.Current);
        }
        while (enumerator.MoveNext());
        return valueStringBuilder.ToString();
    }

References System.array, System.String.Empty, System.Collections.Generic.Dictionary< TKey, TValue >.GetEnumerator(), System.String.JoinCore(), System.list, System.ThrowHelper.ThrowArgumentNullException(), and System.values.