TableSubstitutionRuleGetSubstitutes Method

public IEnumerable<string> GetSubstitutes(
	string originalFontName
)

Public Function GetSubstitutes ( 
	originalFontName As String
) As IEnumerable(Of String)

public:
IEnumerable<String^>^ GetSubstitutes(
	String^ originalFontName
)

member GetSubstitutes : 
        originalFontName : string -> IEnumerable<string> 

Document doc = new Document();

// Create a font settings object for our document
doc.FontSettings = new FontSettings();

// By default we always start with a system font source
Assert.AreEqual(1, doc.FontSettings.GetFontsSources().Length);

SystemFontSource systemFontSource = (SystemFontSource)doc.FontSettings.GetFontsSources()[0];
Assert.AreEqual(FontSourceType.SystemFonts, systemFontSource.Type);
Assert.AreEqual(0, systemFontSource.Priority);

PlatformID pid = Environment.OSVersion.Platform;
bool isWindows = (pid == PlatformID.Win32NT) || (pid == PlatformID.Win32S) || (pid == PlatformID.Win32Windows) || (pid == PlatformID.WinCE);
if (isWindows)
{
    const string fontsPath = @"C:\WINDOWS\Fonts";
    Assert.AreEqual(fontsPath.ToLower(), SystemFontSource.GetSystemFontFolders().FirstOrDefault()?.ToLower());
}

foreach (string systemFontFolder in SystemFontSource.GetSystemFontFolders())
{
    Console.WriteLine(systemFontFolder);
}

// Set a font that exists in the windows fonts directory as a substitute for one that doesn't
doc.FontSettings.SubstitutionSettings.FontInfoSubstitution.Enabled = true;
doc.FontSettings.SubstitutionSettings.TableSubstitution.AddSubstitutes("Kreon-Regular", new string[] { "Calibri" });

Assert.AreEqual(1, doc.FontSettings.SubstitutionSettings.TableSubstitution.GetSubstitutes("Kreon-Regular").Count());
Assert.Contains("Calibri", doc.FontSettings.SubstitutionSettings.TableSubstitution.GetSubstitutes("Kreon-Regular").ToArray());

// Alternatively, we could add a folder font source in which the corresponding folder contains the font
FolderFontSource folderFontSource = new FolderFontSource(FontsDir, false);
doc.FontSettings.SetFontsSources(new FontSourceBase[] { systemFontSource, folderFontSource });
Assert.AreEqual(2, doc.FontSettings.GetFontsSources().Length);

// Resetting the font sources still leaves us with the system font source as well as our substitutes
doc.FontSettings.ResetFontSources();

Assert.AreEqual(1, doc.FontSettings.GetFontsSources().Length);
Assert.AreEqual(FontSourceType.SystemFonts, doc.FontSettings.GetFontsSources()[0].Type);
Assert.AreEqual(1, doc.FontSettings.SubstitutionSettings.TableSubstitution.GetSubstitutes("Kreon-Regular").Count());

// Create a blank document and a new FontSettings object
Document doc = new Document();
FontSettings fontSettings = new FontSettings();
doc.FontSettings = fontSettings;

// Create a new table substitution rule and load the default Windows font substitution table
TableSubstitutionRule tableSubstitutionRule = fontSettings.SubstitutionSettings.TableSubstitution;

// If we select fonts exclusively from our own folder, we will need a custom substitution table
FolderFontSource folderFontSource = new FolderFontSource(FontsDir, false);
fontSettings.SetFontsSources(new FontSourceBase[] { folderFontSource });

// There are two ways of loading a substitution table from a file in the local file system
// 1: Loading from a stream
using (FileStream fileStream = new FileStream(MyDir + "Font substitution rules.xml", FileMode.Open))
{
    tableSubstitutionRule.Load(fileStream);
}

// 2: Load directly from file
tableSubstitutionRule.Load(MyDir + "Font substitution rules.xml");

// Since we no longer have access to "Arial", our font table will first try substitute it with "Nonexistent Font", which we don't have,
// and then with "Kreon", found in the "MyFonts" folder
Assert.AreEqual(new[] { "Missing Font", "Kreon" }, tableSubstitutionRule.GetSubstitutes("Arial").ToArray());

// If we find this substitution table lacking, we can also expand it programmatically
// In this case, we add an entry that substitutes "Times New Roman" with "Arvo"
Assert.Null(tableSubstitutionRule.GetSubstitutes("Times New Roman"));
tableSubstitutionRule.AddSubstitutes("Times New Roman", "Arvo");
Assert.AreEqual(new[] { "Arvo" }, tableSubstitutionRule.GetSubstitutes("Times New Roman").ToArray());

// We can add a secondary fallback substitute for an existing font entry with AddSubstitutes()
// In case "Arvo" is unavailable, our table will look for "M+ 2m"
tableSubstitutionRule.AddSubstitutes("Times New Roman", "M+ 2m");
Assert.AreEqual(new[] { "Arvo", "M+ 2m" }, tableSubstitutionRule.GetSubstitutes("Times New Roman").ToArray());

// SetSubstitutes() can set a new list of substitute fonts for a font
tableSubstitutionRule.SetSubstitutes("Times New Roman", new[] { "Squarish Sans CT", "M+ 2m" });
Assert.AreEqual(new[] { "Squarish Sans CT", "M+ 2m" }, tableSubstitutionRule.GetSubstitutes("Times New Roman").ToArray());

// TO demonstrate substitution, write text in fonts we have no access to and render the result in a PDF
DocumentBuilder builder = new DocumentBuilder(doc);
builder.Font.Name = "Arial";
builder.Writeln("Text written in Arial, to be substituted by Kreon.");

builder.Font.Name = "Times New Roman";
builder.Writeln("Text written in Times New Roman, to be substituted by Squarish Sans CT.");

doc.Save(ArtifactsDir + "Font.TableSubstitutionRule.Custom.pdf");