private string ProcessExpression(StringBuilder expressionBuffer, ViewDataContainer ViewData)
{
if (expressionBuffer.Length > 0)
{
string expression = expressionBuffer.ToString();
expressionBuffer.Clear();
string[] parts = expression.Split(':');
if (!ViewData.TryGet(parts[parts.Length - 1], out string value))
{
throw new Exception("A view expression referred to a key that does not exist in the view data.");
}
for (int i = parts.Length - 2; i >= 0; i--)
{
value = PerformExpressionMethod(parts[i], value);
}
return(value);
}
else
{
throw new Exception("View contained an empty expression.");
}
}
private string ProcessExpression(StringBuilder expressionBuffer, ViewDataContainer ViewData)
{
if (expressionBuffer.Length > 0)
{
string expression = expressionBuffer.ToString();
expressionBuffer.Clear();
string[] parts = expression.Split(':');
string value = ViewData.Get(parts[parts.Length - 1]);
if (string.IsNullOrEmpty(value))
{
return("");
}
for (int i = parts.Length - 2; i >= 0; i--)
{
value = PerformExpressionMethod(parts[i], value);
}
return(value);
}
else
{
throw new Exception("View contained an empty expression.");
}
}
/// <summary>
/// Processes the specified text as a view and sets this result body. Do not call this unless the constructor you used says to do so.
/// </summary>
/// <param name="viewText">The view's text.</param>
/// <param name="ViewData">A ViewDataContainer containing values for expressions found within the view.</param>
/// <returns></returns>
public void ProcessView(string viewText, ViewDataContainer ViewData)
{
if (ViewData != null)
{
StringBuilder sb = new StringBuilder(viewText.Length);
StringBuilder expressionBuffer = new StringBuilder();
ViewParseState state = ViewParseState.HTML;
bool expressionStartedWithParenthesis = false;
foreach (char c in viewText)
{
if (state == ViewParseState.HTML)
{
if (c == '@')
{
state = ViewParseState.Expression;
}
else
{
sb.Append(c);
}
}
else if (state == ViewParseState.Expression)
{
if (c == '@')
{
if (expressionBuffer.Length == 0)
{
// This was a sequence of two adjacent '@' characters, which is output as one literal '@' character.
state = ViewParseState.HTML;
sb.Append(c);
}
else
{
// New '@' ends the previous expression and starts a new one.
sb.Append(ProcessExpression(expressionBuffer, ViewData));
}
}
else if (expressionBuffer.Length == 0 && c == '(')
{
// Expressions can be within parenthesis in order
// to mark their end to allow for cases like:
// "@(AppRoot)images/icon.jpg"
expressionStartedWithParenthesis = true;
}
else if ((c >= 'a' && c <= 'z') ||
(c >= 'A' && c <= 'Z') ||
(c >= '0' && c <= '9') ||
c == '_' ||
c == ':')
{
// This character gets added to the expression.
expressionBuffer.Append(c);
}
else
{
if (expressionStartedWithParenthesis && c != ')')
{
throw new Exception("Expression began with opening parenthesis but did not end with closing parenthesis.");
}
// This character ends the expression.
state = ViewParseState.HTML;
sb.Append(ProcessExpression(expressionBuffer, ViewData));
if (!expressionStartedWithParenthesis)
{
sb.Append(c);
}
expressionStartedWithParenthesis = false;
}
}
}
if (state == ViewParseState.Expression)
{
sb.Append(ProcessExpression(expressionBuffer, ViewData));
}
viewText = sb.ToString();
}
BodyStr = viewText;
}
/// <summary>
/// Contructs a ViewResult from the specified file.
/// </summary>
/// <param name="filePath">Path to a text file containing the view content.</param>
/// <param name="ViewData">A ViewDataContainer containing values for expressions found within the view.</param>
public ViewResult(string filePath, ViewDataContainer ViewData) : base(null)
{
string text = File.ReadAllText(filePath);
ProcessView(text, ViewData);
}
public ViewBagContainer(ViewDataContainer ViewData)
{
this.ViewData = ViewData;
}
/// <summary>
/// Processes the specified text as a view and sets this result body.
/// </summary>
/// <param name="viewText">The view's text.</param>
/// <param name="ViewData">A ViewDataContainer containing values for expressions found within the view.</param>
/// <returns></returns>
public void ProcessView(string viewText, ViewDataContainer ViewData)
{
if (ViewData != null)
{
StringBuilder sb = new StringBuilder(viewText.Length);
StringBuilder expressionBuffer = new StringBuilder();
ViewParseState state = ViewParseState.HTML;
foreach (char c in viewText)
{
if (state == ViewParseState.HTML)
{
if (c == '@')
{
state = ViewParseState.Expression;
}
else
{
sb.Append(c);
}
}
else if (state == ViewParseState.Expression)
{
if (c == '@')
{
if (expressionBuffer.Length == 0)
{
// This was a sequence of two adjacent '@' characters, which is output as one literal '@' character.
state = ViewParseState.HTML;
sb.Append(c);
}
else
{
// New '@' ends the previous expression and starts a new one.
sb.Append(ProcessExpression(expressionBuffer, ViewData));
}
}
else if ((c >= 'a' && c <= 'z') ||
(c >= 'A' && c <= 'Z') ||
(c >= '0' && c <= '9') ||
c == '_' ||
c == ':')
{
// This character gets added to the expression.
expressionBuffer.Append(c);
}
else
{
// This character ends the expression.
state = ViewParseState.HTML;
sb.Append(ProcessExpression(expressionBuffer, ViewData));
sb.Append(c);
}
}
}
if (state == ViewParseState.Expression)
{
sb.Append(ProcessExpression(expressionBuffer, ViewData));
}
viewText = sb.ToString();
}
Body = Encoding.UTF8.GetBytes(viewText);
}
