CompactExpressionParser

A lightweight and simple expression parser for .NET. Distributed as library and C# source code package.

Expression Syntax

For the most part, the expression syntax is pre-defined by the implementation. However, the unary and binary operators are user-defined. Here are some examples of valid expressions:

"Hello World!"

MD5("Hello World!")

#("Hello World!")

#"Hello World!"

(5 + 2) >= 7

status IN [1,2,3,7]

Literals

true, false are parsed into boolean values. "Hello World!", "Escaped\nsequence with \u07 special chars." are string literals. 192, 0.91, -19 are numeric literals, which may be either of type double or long.

Identifier

myIdentifier (anything starting with a letter, which is not true, false, or one of the user-defined operators)

Binary operators

5 + 6, 5 == 6

Unary operators

!5, ~"example", #myIdentifier

Member access

myIdentifier.myProperty, "example".length, getObject().myMethod()

Invocations

hashCode("with this string"), hashCode("with this string", salt, true)

Subscripts

myList[0], myList["id"], myList[ (5 + offset) ]

Lists

[1, 2, 3], [var1, 7+1, [1,2,3]]