Old topic, but considering this is one of the first threads showing up when googling, here is an updated solution. You can use Roslyn’s new Scripting API to evaluate expressions. If you are using NuGet, just add a dependency to Microsoft.CodeAnalysis.CSharp.Scripting. To evaluate the examples you provided, it is as simple as: var result = … Read more
For read-only controls they are the same. For 2 way databinding, using a datasource in which you want to update, insert, etc with declarative databinding, you’ll need to use Bind. Imagine for example a GridView with a ItemTemplate and EditItemTemplate. If you use Bind or Eval in the ItemTemplate, there will be no difference. If … Read more
Mhh, you could use the Function() constructor: function evil(fn) { return new Function(‘return ‘ + fn)(); } console.log(evil(’12/5*9+9.4*2’)); // => 40.4
Most of the arguments against eval(parse(…)) arise not because of security concerns, after all, no claims are made about R being a safe interface to expose to the Internet, but rather because such code is generally doing things that can be accomplished using less obscure methods, i.e. methods that are both quicker and more human … Read more
First of all, you should avoid using this; C# is a strongly-typed language, so take advantage of the type safety and performance advantages that accompany that aspect. If you have a legitimate reason to get and set the value of a property dynamically (in other words, when the type and/or property name is not able … Read more
You can use 1) pd.eval(), 2) df.query(), or 3) df.eval(). Their various features and functionality are discussed below. Examples will involve these dataframes (unless otherwise specified). np.random.seed(0) df1 = pd.DataFrame(np.random.choice(10, (5, 4)), columns=list(‘ABCD’)) df2 = pd.DataFrame(np.random.choice(10, (5, 4)), columns=list(‘ABCD’)) df3 = pd.DataFrame(np.random.choice(10, (5, 4)), columns=list(‘ABCD’)) df4 = pd.DataFrame(np.random.choice(10, (5, 4)), columns=list(‘ABCD’)) 1) pandas.eval This is … Read more
I would be cautious in calling eval() pure evil. Dynamic evaluation is a powerful tool and can sometimes be a life saver. With eval() one can work around shortcomings of PHP (see below). The main problems with eval() are: Potential unsafe input. Passing an untrusted parameter is a way to fail. It is often not … Read more
The difference between (1,eval) and plain old eval is that the former is a value and the latter is an lvalue. It would be more obvious if it were some other identifier: var x; x = 1; (1, x) = 1; // syntax error, of course! That is (1,eval) is an expression that yields eval … Read more
No, they are not the same. eval() evaluates a string as a JavaScript expression within the current execution scope and can access local variables. new Function() parses the JavaScript code stored in a string into a function object, which can then be called. It cannot access local variables because the code runs in a separate … Read more
[*] There’s more to this problem than meets the eye. We’ll start with the obvious: eval has the potential to execute “dirty” data. Dirty data is any data that has not been rewritten as safe-for-use-in-situation-XYZ; in our case, it’s any string that has not been formatted so as to be safe for evaluation. Sanitizing data … Read more