private static Expression <Func <TSource, TDest> > BuildExpression <TDest>(Dictionary <int, int> parameterIndexs,
int index = 0)
{
var cachedExp = GetCachedExpression <TDest>();
if (cachedExp != null)
{
return(cachedExp);
}
lock (ExpressionCache)
{
cachedExp = GetCachedExpression <TDest>();
if (cachedExp != null)
{
return(cachedExp);
}
var config = GetCachedConfig(typeof(TSource), typeof(TDest));
var hasConfig = config != null;
var sourceProperties = typeof(TSource).GetProperties();
var destinationProperties = typeof(TDest).GetProperties().Where(dest => dest.CanWrite);
if (hasConfig)
{
destinationProperties =
destinationProperties.Where(dest => !config.IgnoreMembers.Contains(dest.Name));
}
var parameterExpression =
Expression.Parameter(typeof(TSource), string.Concat("src", typeof(TSource).Name, index));
var bindings = destinationProperties
.Select(destinationProperty => HasCustomExpression(config, destinationProperty)
? BuildCustomBinding(config, parameterExpression, destinationProperty)
: BuildBinding(parameterExpression, destinationProperty, sourceProperties, config,
parameterIndexs, index)
)
.Where(binding => binding != null);
var expression =
Expression.Lambda <Func <TSource, TDest> >(
Expression.MemberInit(Expression.New(typeof(TDest)), bindings), parameterExpression);
var key = GetCacheKey <TDest>();
ExpressionCache.Add(key, expression);
return(expression);
}
}
