Char.IsSurrogatePair Method (Char, Char)
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Indicates whether the two specified Char objects form a surrogate pair.
Assembly: mscorlib (in mscorlib.dll)
'Declaration Public Shared Function IsSurrogatePair ( _ highSurrogate As Char, _ lowSurrogate As Char _ ) As Boolean
Return Value
Type: System.Booleantrue if the numeric value of the highSurrogate parameter ranges from U+D800 through U+DBFF, and the numeric value of the lowSurrogate parameter ranges from U+DC00 through U+DFFF; otherwise, false.
Ordinarily, a single character is represented by a single 16-bit Unicode code unit. UTF-16 encoding also supports surrogate pairs, which allow a single abstract character to be represented by two 16-bit code units. The first code unit, whose value can range from U+D800 to U+DBFF, is the high surrogate. The second code unit, whose value can range from U+DC00 to U+DFFF, is the low surrogate. Individual surrogate code units have no interpretation of their own. For more information about surrogates and the Unicode Standard, see the Unicode home page.
The following example demonstrates the IsSurrogatePair method.
' This example demonstrates the Char.IsSurrogatePair() method Class Example Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock) Dim cHigh As Char = ChrW(&HD800) Dim cLow As Char = ChrW(&HDC00) Dim s1 = New [String](New Char() {"a"c, ChrW(&HD800), ChrW(&HDC00), "z"c}) Dim divider As String = [String].Concat(vbCrLf, _ New [String]("-"c, 70), _ vbCrLf) outputBlock.Text &= vbCrLf outputBlock.Text &= String.Format("Hexadecimal code point of the character, cHigh: {0:X4}", AscW(cHigh)) & vbCrLf outputBlock.Text &= String.Format("Hexadecimal code point of the character, cLow: {0:X4}", AscW(cLow)) & vbCrLf outputBlock.Text &= vbCrLf outputBlock.Text &= String.Format("Characters in string, s1: 'a', high surrogate, low surrogate, 'z'") & vbCrLf outputBlock.Text &= String.Format("Hexadecimal code points of the characters in string, s1: ") & vbCrLf Dim i As Integer For i = 0 To s1.Length - 1 outputBlock.Text &= String.Format("s1({0}) = {1:X4} ", i, AscW(s1.Chars(i))) & vbCrLf Next i outputBlock.Text &= divider & vbCrLf outputBlock.Text &= "Is each of the following pairs of characters a surrogate pair?" & vbCrLf outputBlock.Text &= String.Format("C1) cHigh and cLow? - {0}", [Char].IsSurrogatePair(cHigh, cLow)) & vbCrLf outputBlock.Text &= String.Format("C2) s1(0) and s1(1)? - {0}", [Char].IsSurrogatePair(s1, 0)) & vbCrLf outputBlock.Text &= String.Format("C3) s1(1) and s1(2)? - {0}", [Char].IsSurrogatePair(s1, 1)) & vbCrLf outputBlock.Text &= String.Format("C4) s1(2) and s1(3)? - {0}", [Char].IsSurrogatePair(s1, 2)) & vbCrLf outputBlock.Text &= divider & vbCrLf End Sub 'Main End Class 'Sample ' 'This example produces the following results: ' 'Hexadecimal code point of the character, cHigh: D800 'Hexadecimal code point of the character, cLow: DC00 ' 'Characters in string, s1: 'a', high surrogate, low surrogate, 'z' 'Hexadecimal code points of the characters in string, s1: 's1(0) = 0061 's1(1) = D800 's1(2) = DC00 's1(3) = 007A ' '---------------------------------------------------------------------- ' 'Is each of the following pairs of characters a surrogate pair? 'C1) cHigh and cLow? - True 'C2) s1(0) and s1(1)? - False 'C3) s1(1) and s1(2)? - True 'C4) s1(2) and s1(3)? - False ' '----------------------------------------------------------------------