Is there a way to programmatically determine if a font file has a specific Unicode Glyph?

Question

I\'m working on a project that generates PDFs that can contain fairly complex math and science formulas. The text is rendered in Times New Roman, which has pretty good Unic

Answer 1

I have done this with just a VB.Net Unit Test and no WIN32 API calls. It includes code to check specific characters U+2026 (ellipsis) & U+2409 (HTab), and also returns # of characters (and low and high values) that have glyphs. I was only interested in Monospace fonts, but easy enough to change ...

    Dim fnt As System.Drawing.Font, size_M As Drawing.Size, size_i As Drawing.Size, size_HTab As Drawing.Size, isMonospace As Boolean
    Dim ifc = New Drawing.Text.InstalledFontCollection
    Dim bm As Drawing.Bitmap = New Drawing.Bitmap(640, 64), gr = Drawing.Graphics.FromImage(bm)
    Dim tf As Windows.Media.Typeface, gtf As Windows.Media.GlyphTypeface = Nothing, ok As Boolean, gtfName = ""

    For Each item In ifc.Families
        'TestContext_WriteTimedLine($"N={item.Name}.")
        fnt = New Drawing.Font(item.Name, 24.0)
        Assert.IsNotNull(fnt)

        tf = New Windows.Media.Typeface(item.Name)
        Assert.IsNotNull(tf, $"item.Name={item.Name}")

        size_M = System.Windows.Forms.TextRenderer.MeasureText("M", fnt)
        size_i = System.Windows.Forms.TextRenderer.MeasureText("i", fnt)
        size_HTab = System.Windows.Forms.TextRenderer.MeasureText(ChrW(&H2409), fnt)
        isMonospace = size_M.Width = size_i.Width
        Assert.AreEqual(size_M.Height, size_i.Height, $"fnt={fnt.Name}")

        If isMonospace Then

            gtfName = "-"
            ok = tf.TryGetGlyphTypeface(gtf)
            If ok Then
                Assert.AreEqual(True, ok, $"item.Name={item.Name}")
                Assert.IsNotNull(gtf, $"item.Name={item.Name}")
                gtfName = $"{gtf.FamilyNames(Globalization.CultureInfo.CurrentUICulture)}"

                Assert.AreEqual(True, gtf.CharacterToGlyphMap().ContainsKey(AscW("M")), $"item.Name={item.Name}")
                Assert.AreEqual(True, gtf.CharacterToGlyphMap().ContainsKey(AscW("i")), $"item.Name={item.Name}")

                Dim t = 0, nMin = &HFFFF, nMax = 0
                For n = 0 To &HFFFF
                    If gtf.CharacterToGlyphMap().ContainsKey(n) Then
                        If n < nMin Then nMin = n
                        If n > nMax Then nMax = n
                        t += 1
                    End If
                Next
                gtfName &= $",[x{nMin:X}-x{nMax:X}]#{t}"

                ok = gtf.CharacterToGlyphMap().ContainsKey(AscW(ChrW(&H2409)))
                If ok Then
                    gtfName &= ",U+2409"
                End If
                ok = gtf.CharacterToGlyphMap().ContainsKey(AscW(ChrW(&H2026)))
                If ok Then
                    gtfName &= ",U+2026"
                End If
            End If

            Debug.WriteLine($"{IIf(isMonospace, "*M*", "")} N={fnt.Name}, gtf={gtfName}.")
            gr.Clear(Drawing.Color.White)
            gr.DrawString($"Mi{ChrW(&H2409)} {fnt.Name}", fnt, New Drawing.SolidBrush(Drawing.Color.Black), 10, 10)
            bm.Save($"{fnt.Name}_MiHT.bmp")
        End If
    Next

The output was

M N=Consolas, gtf=Consolas,[x0-xFFFC]#2488,U+2026.

M N=Courier New, gtf=Courier New,[x20-xFFFC]#3177,U+2026.

M N=Lucida Console, gtf=Lucida Console,[x20-xFB02]#644,U+2026.

M N=Lucida Sans Typewriter, gtf=Lucida Sans Typewriter,[x20-xF002]#240,U+2026.

M N=MingLiU-ExtB, gtf=MingLiU-ExtB,[x0-x2122]#212.

M N=MingLiU_HKSCS-ExtB, gtf=MingLiU_HKSCS-ExtB,[x0-x2122]#212.

M N=MS Gothic, gtf=MS Gothic,[x0-xFFEE]#15760,U+2026.

M N=NSimSun, gtf=NSimSun,[x20-xFFE5]#28737,U+2026.

M N=OCR A Extended, gtf=OCR A Extended,[x20-xF003]#248,U+2026.

M N=SimSun, gtf=SimSun,[x20-xFFE5]#28737,U+2026.

M N=SimSun-ExtB, gtf=SimSun-ExtB,[x20-x7F]#96.

M N=Webdings, gtf=Webdings,[x20-xF0FF]#446.