Text Matching Expressions

Text matching expressions in EyeAuras are flexible tools for checking text-based conditions defined by the user. Three evaluator types are available: Regex, Text, and Lambda.

You may encounter them in Text Search, Network Message, Telegram Message, and some other trigger types.

Text evaluator

The Text evaluator compares input directly against the specified text. It is case-sensitive by default, but you can enable case-insensitive matching if needed.

Examples:

• Match Hello, world
  Match text: Hello, world
  This matches only the exact string Hello, world.

• Match a numeric string
  Match text: 12345
  This matches the string 12345. Note that it will not match the number 12345 entered without quotes.

• Case-insensitive match
  Match text: HELLO
  With case-insensitive mode enabled, this matches hello, Hello, HELLO, and so on.

• Match a sentence
  Match text: The quick brown fox jumps over the lazy dog
  This matches the full sentence exactly as written.

Regex evaluator

The Regex evaluator lets you use regular expressions for more advanced and flexible text matching.

Examples:

• Match any number
  Regex: \d+
  This matches any string representing a number, such as 123, 45678, and so on.

• Match any word
  Regex: \b\w+\b
  This matches any string representing a word, such as Hello, World, and so on.

• Match any two letters
  Regex: \b[a-zA-Z]{2}\b
  This matches any string containing exactly two letters, such as ab, cd, and so on.

• Match any three digits
  Regex: \b\d{3}\b
  This matches any string containing exactly three digits, such as 123, 456, and so on.

• Match any word that starts with a specific letter
  Regex: \bH\w*\b
  This matches any word that starts with H, such as Hello, Hi, and so on.

• Match any word that ends with a specific letter
  Regex: \b\w*e\b
  This matches any word that ends with e, such as code, node, and so on.

Lambda evaluator

The Lambda evaluator is a powerful tool that lets you write C# lambda expressions. It effectively converts a string into a boolean value based on the conditions you define, which gives you a very wide range of possibilities.

For example, you can create a lambda expression to check whether a string is empty, whether it contains specific characters, or whether it can be converted into a number within a certain range.

Examples:

• Check whether a string is empty
  Lambda expression: text => string.IsNullOrEmpty(text)
  This returns True for an empty string or null, and False otherwise.

• Check whether a string contains Hello
  Lambda expression: text => text.Contains("Hello")
  This returns True if the string contains Hello, and False otherwise.

• Check whether the string length is less than 5
  Lambda expression: text => text.Length < 5
  This returns True if the string length is less than 5, and False otherwise.

• Check whether the string can be converted to a number within a specific range
  Lambda expression: text => double.Parse(text) >= 1 && double.Parse(text) <= 100
  This returns True if the string can be converted to a number from 1 to 100, and False otherwise.

Testing mode

Testing mode is a useful feature that lets you enter a string value and verify that your expression works as expected, reducing the chance of errors. You can use it to fine-tune expressions for your needs.

Keep in mind that all evaluators work with strings and are compatible with any Unicode-supported language. There are no restrictions on the types of expressions you can create, and EyeAuras will warn you if an expression is invalid.