TextWriter _writer; // all output is sent here
#endregion Fields
#region Constructors
/// <summary>
/// create template manager using a template
/// </summary>
public TemplateHelper(Template template)
{
this._mainTemplate = template;
this._currentTemplate = template;
Init();
}
public Template(string name, List<Element> elements, Template parent)
{
this.name = name;
this.elements = elements;
this.parent = parent;
InitTemplates();
}
/// <summary>
/// go thru all tags and see if they are template tags and add
/// them to this.templates collection
/// </summary>
private void InitTemplates()
{
this.templates = new Dictionary<string, Template>(StringComparer.InvariantCultureIgnoreCase);
foreach (Element elem in elements)
{
if (elem is Tag)
{
Tag tag = (Tag)elem;
if (string.Compare(tag.Name, "template", true) == 0)
{
Expression ename = tag.AttributeValue("name");
string tname;
if (ename is StringLiteral)
tname = ((StringLiteral)ename).Content;
else
tname = "?";
Template template = new Template(tname, tag.InnerElements, this);
templates[tname] = template;
}
}
}
}
protected void ProcessTemplate(string name, Tag tag)
{
Template useTemplate = _currentTemplate.FindTemplate(name);
if (useTemplate == null)
{
string msg = string.Format("Template '{0}' not found", name);
WriteError(msg, tag.Line, tag.Col);
return;
}
// process inner elements and save content
TextWriter saveWriter = _writer;
_writer = new StringWriter();
string content = string.Empty;
try
{
ProcessElements(tag.InnerElements);
content = _writer.ToString();
}
catch
{
return; // on error, do not do tag inclusion
}
finally
{
_writer = saveWriter;
}
Template saveTemplate = _currentTemplate;
_variables = new VariableScope(_variables);
_variables["innerText"] = content;
try
{
foreach (TagAttribute attrib in tag.Attributes)
{
object val = EvalExpression(attrib.Expression);
_variables[attrib.Name] = val;
}
_currentTemplate = useTemplate;
ProcessElements(_currentTemplate.Elements);
}
finally
{
_variables = _variables.Parent;
_currentTemplate = saveTemplate;
}
}
/// <summary>
/// processes current template and sends output to writer
/// </summary>
/// <param name="writer"></param>
public void Process(TextWriter writer)
{
this._writer = writer;
this._currentTemplate = _mainTemplate;
ProcessElements(_mainTemplate.Elements);
}
/// <summary>
/// adds template that can be used within execution
/// </summary>
/// <param name="template"></param>
public void AddTemplate(Template template)
{
_mainTemplate.Templates.Add(template.Name, template);
}