isNumber

returns true if a value is a number, false if it is not.

# Metadata

Platforms: desktop, server, mobile OS: mac, windows, linux, ios, android Introduced: 1.0 Security:

# Syntax

the isNumber of value

# Params

- value : Any source of value.

# Examples

isNumber(8) -- returns true

isNumber(1+5) -- returns true

isNumber(foo) -- returns false

# Description

Use the isNumber function to determine whether a value is a number. For example, attempting to do an arithmetic operation on a value that's not a number causes an error. You can check the value beforehand to prevent this.

This function exists for compatibility with imported SuperCard projects. You can use the is a operator to validate numbers, as well as other data types.

# Tags

math,

# See

- **operator:** is a - **function:** value, exists - **glossary:** operation, operator, validate, return, error - **control structure:** function