/// <summary>
/// Visits the given expression.
/// </summary>
/// <param name="expression"> The expression to visit. </param>
/// <returns>
/// An Expression.
/// </returns>
public override Expression Visit(Expression expression)
{
var translatedExpression = _compositeExpressionFragmentTranslator.Translate(expression);
if (translatedExpression != null &&
translatedExpression != expression)
{
return(Visit(translatedExpression));
}
// ReSharper disable once ConditionIsAlwaysTrueOrFalse
if (expression != null &&
(expression.NodeType == ExpressionType.Convert ||
expression.NodeType == ExpressionType.Negate ||
expression.NodeType == ExpressionType.New))
{
return(base.Visit(expression));
}
var isTopLevelProjection = _isTopLevelProjection;
_isTopLevelProjection = false;
try
{
return(base.Visit(expression));
}
finally
{
_isTopLevelProjection = isTopLevelProjection;
}
}
/// <summary>
/// Delegates everything that is not fragments, converts, negates, and new with
/// a top level return marker
/// </summary>
/// <param name="expression"></param>
/// <returns></returns>
public override Expression Visit(Expression expression)
{
var translated = _compositeExpressionFragmentTranslator.Translate(expression);
if (translated != null && translated != expression)
{
return(Visit(translated));
}
if (expression != null &&
(expression.NodeType == ExpressionType.Convert ||
expression.NodeType == ExpressionType.Negate ||
expression.NodeType == ExpressionType.New))
{
return(base.Visit(expression));
}
var isTopLevelReturn = _isTopLevelReturn;
_isTopLevelReturn = false;
try
{
return(base.Visit(expression));
}
finally
{
_isTopLevelReturn = isTopLevelReturn;
}
}
/// <summary>
/// 将表达式调度到此类中更专用的访问方法之一。
/// </summary>
/// <returns>
/// 如果修改了该表达式或任何子表达式，则为修改后的表达式；否则返回原始表达式。
/// </returns>
/// <param name="expression">要访问的表达式。</param>
public override Expression Visit(Expression expression)
{
var translatedExpression = _fragmentTranslator.Translate(expression);
if (translatedExpression != null && translatedExpression != expression)
{
return(Visit(translatedExpression));
}
return(base.Visit(expression));
}
public override Expression Visit(Expression expression)
{
var translatedExpression = _compositeExpressionFragmentTranslator.Translate(expression);
if ((translatedExpression != null) &&
(translatedExpression != expression))
{
return(Visit(translatedExpression));
}
return(base.Visit(expression));
}