DynamicExpression parser can't parse when there is a dot in a string

[YeskaNova]

1. Description

I need to parse a condition that checks that the Name of an entity is "System.Int32" , but because of the dot, I get an error. Could you see why is that happening please? It seems to me that it's a very simple situation.

2. Exception

Unhandled exception. '.' or '(' or string literal expected (at index 19)

3. Fiddle

https://dotnetfiddle.net/hdL13r

[StefH]

Hello @YeskaNova,

In your example code, the string value in the expression, System.Int32 is parsed as a Type : Int32.

To work around this:

1]
Set the ParsingConfig SupportCastingToFullyQualifiedTypeAsString to false.

2]
Or use the parameterized way from DynamicExpressionParser, see example below:

var expression = DynamicExpressionParser.ParseLambda(typeof(EntityDbo), typeof(bool), "Name == @0", "System.Int32");

#685

[YeskaNova]

Why it tries to interpret something within the string quotes ? isn't that a security issue ?

[StefH]

You mean :

"Name=\"System.Int32\""

?

[YeskaNova]

Yes, this part "System.Int32" is a string token and should not be interpreted by the interpretor.

[StefH]

What do you mean by string token?

The whole purpose from this library is to allow dynamic querying using a string expression, like:

var resultDynamic = context.Customers
     .Where("City == \"Paris\"")
    .ToList();

https://dynamic-linq.net/basic-simple-query

[YeskaNova]

The string token is "System.Int32" .

For example, this code should work:

var resultDynamic = context.Customers
     .Where("City == \"System.Int32\"")
    .ToList();

"Paris" is a string token, and the interpretor should not try to understand what is "inside" the string. Like "1/0" should not be a problem but 1/0 will raise an exception, anything inside a string should not be considered by the interpretor. I don't see any usecase where intepreting inside a string is useful ( and that's not string interpolation )

[StefH]

It will be fixed in next release.

#687

[YeskaNova]

Great, thanks a lot!