Create StringFindSubstring.cpp

String Manipulation/StringFindSubstring.cpp

@@ -0,0 +1,64 @@
+INT StringCompareStringRegionA(PCHAR String1, PCHAR String2, SIZE_T Count)
+{
+	UCHAR Block1, Block2;
+	while (Count-- > 0)
+	{
+		Block1 = (UCHAR)*String1++;
+		Block2 = (UCHAR)*String2++;
+
+		if (Block1 != Block2)
+			return Block1 - Block2;
+
+		if (Block1 == '\0')
+			return 0;
+	}
+
+	return 0;
+}
+
+INT StringCompareStringRegionW(PWCHAR String1, PWCHAR String2, SIZE_T Count)
+{
+	UCHAR Block1, Block2;
+	while (Count-- > 0)
+	{
+		Block1 = (UCHAR)*String1++;
+		Block2 = (UCHAR)*String2++;
+
+		if (Block1 != Block2)
+			return Block1 - Block2;
+
+		if (Block1 == '\0')
+			return 0;
+	}
+
+	return 0;
+}
+
+
+PCHAR StringFindSubstringA(PCHAR String1, PCHAR String2)
+{
+	PCHAR pPointer = String1;
+	DWORD Length = (DWORD)StringLengthA(String2);
+
+	for (; (pPointer = StringLocateCharA(pPointer, *String2)) != 0; pPointer++)
+	{
+		if (StringCompareStringRegionA(pPointer, String2, Length) == 0)
+			return (PCHAR)pPointer;
+	}
+
+	return NULL;
+}
+
+PWCHAR StringFindSubstringW(PWCHAR String1, PWCHAR String2)
+{
+	PWCHAR pPointer = String1;
+	DWORD Length = (DWORD)StringLengthW(String2);
+
+	for (; (pPointer = StringLocateCharW(pPointer, *String2)) != 0; pPointer++)
+	{
+		if (StringCompareStringRegionW(pPointer, String2, Length) == 0)
+			return (PWCHAR)pPointer;
+	}
+
+	return NULL;
+}