Object CalcSimpleExpression(String expression)
{
var lexpr = DynamicParser.ParseLambda(null, expression);
var lambda = lexpr.Compile();
return(lambda.DynamicInvoke());
}
public T CalcExpression <T>(ExpandoObject root, String expression)
{
Object result;
if (_lambdas != null && _lambdas.TryGetValue(expression, out Delegate expr))
{
result = expr.DynamicInvoke(root);
}
else
{
if (_lambdas == null)
{
_lambdas = new Dictionary <String, Delegate>();
}
var prms = new ParameterExpression[] {
Expression.Parameter(typeof(ExpandoObject), "Root")
};
var lexpr = DynamicParser.ParseLambda(prms, expression);
expr = lexpr.Compile();
_lambdas.Add(expression, expr);
result = expr.DynamicInvoke(root);
}
if (result == null)
{
return(default);
Object CalcExpression(String expression, String prm, Object value)
{
var prms = new ParameterExpression[] {
Expression.Parameter(typeof(Object), prm)
};
var lexpr = DynamicParser.ParseLambda(prms, expression);
var lambda = lexpr.Compile();
return(lambda.DynamicInvoke(value));
}
public T CalcExpression <T>(ExpandoObject root, String expression)
{
Object result = null;
if (_lambdas != null && _lambdas.TryGetValue(expression, out Delegate expr))
{
result = expr.DynamicInvoke(root);
}
else
{
if (_lambdas == null)
{
_lambdas = new Dictionary <String, Delegate>();
}
var prms = new ParameterExpression[] {
Expression.Parameter(typeof(ExpandoObject), "Root")
};
var lexpr = DynamicParser.ParseLambda(prms, expression);
expr = lexpr.Compile();
_lambdas.Add(expression, expr);
result = expr.DynamicInvoke(root);
}
if (result == null)
{
return(default(T));
}
if (result is T resultT)
{
return(resultT);
}
var tp = typeof(T);
if (tp.IsNullableType())
{
tp = Nullable.GetUnderlyingType(tp);
}
return((T)Convert.ChangeType(result, tp));
}