private Expression Prepare(Expression cachedExpression, ParameterBag parameters)
{
Expression result;
if (parameters.Any())
{
var visitor = new ConstantExpressionReplacementVisitor(parameters);
result = visitor.Visit(cachedExpression);
}
else
{
result = cachedExpression;
}
// perform null-propagation if this feature is enabled.
if (_configurationProvider.EnableNullPropagationForQueryMapping)
{
var nullVisitor = new NullsafeQueryRewriter();
return(nullVisitor.Visit(result));
}
return(result);
}
private Expression Prepare(Expression cachedExpression, object parameters)
{
Expression result;
if (parameters != null)
{
var visitor = ParameterExpressionVisitor.Create(parameters);
result = visitor.Visit(cachedExpression);
}
else
{
result = cachedExpression;
}
// perform null-propagation if this feature is enabled.
if (_configurationProvider.EnableNullPropagationForQueryMapping)
{
var nullVisitor = new NullsafeQueryRewriter();
return(nullVisitor.Visit(result));
}
return(result);
}
public Expression CreateMapExpression(Type sourceType, Type destinationType, IDictionary <string, object> parameters = null, params MemberInfo[] membersToExpand)
{
parameters = parameters ?? new Dictionary <string, object>();
var cachedExpression = _expressionCache.GetOrAdd(new ExpressionRequest(sourceType, destinationType, membersToExpand, null));
Expression x = cachedExpression;
if (parameters.Any())
{
var visitor = new ConstantExpressionReplacementVisitor(parameters);
x = visitor.Visit(cachedExpression);
}
// perform null-propagation if this feature is enabled.
if (_configurationProvider.EnableNullPropagationForQueryMapping)
{
var nullVisitor = new NullsafeQueryRewriter();
return(nullVisitor.Visit(x));
}
return(x);
}
public LambdaExpression[] GetMapExpression(Type sourceType, Type destinationType, object parameters, MemberInfo[] membersToExpand)
{
var expressionRequest = new ExpressionRequest(
sourceType ?? throw new ArgumentNullException(nameof(sourceType)),
destinationType ?? throw new ArgumentNullException(nameof(destinationType)),
membersToExpand ?? throw new ArgumentNullException(nameof(membersToExpand)),
null);
var cachedExpressions = _expressionCache.GetOrAdd(expressionRequest);
return(Array.ConvertAll(cachedExpressions, Prepare));
LambdaExpression Prepare(Expression cachedExpression)
{
var result = parameters == null ? cachedExpression : ParameterExpressionVisitor.SetParameters(parameters, cachedExpression);
return((LambdaExpression)(_configurationProvider.EnableNullPropagationForQueryMapping ? NullsafeQueryRewriter.NullCheck(result) : result));
}
}
