Is Functions

Functions for checking the type and other conditions of a given value.

Result := IsSomething(Value , Mode)

There are three categories:

Mode is valid only for IsAlpha, IsAlnum, IsUpper and IsLower. By default, only ASCII letters are considered. To instead perform the check according to the rules of the current user's locale, specify the string "Locale" for the Mode parameter. The default mode can also be used by specifying 0 or 1.

Type

Check the type of a value, or whether a string can be interpreted as a value of that type.

Function Description
IsInteger True if Value is an integer or a purely numeric string (decimal or hexadecimal) without a decimal point. Leading and trailing spaces and tabs are allowed. The string may start with a plus or minus sign and must not be empty.
IsFloat True if Value is a floating point number or a purely numeric string containing a decimal point. Leading and trailing spaces and tabs are allowed. The string may start with a plus sign, minus sign, or decimal point and must not be empty.
IsNumber True if IsInteger(Value) or IsFloat(Value) is true.
IsObject True if Value is an object. This includes objects derived from Object, prototype objects such as 0.base, and COM objects, but not numbers or strings.

Misc

Check miscellaneous conditions based on a given value or variable reference.

Function Description
IsLabel True if Value is the name of a label defined within the current scope.
IsSet True if the variable Value has been assigned a value.
IsSetRef True if the VarRef contained by Value has been assigned a value.

String

Check whether a string matches a specific pattern. Value must be a string, otherwise a TypeError is thrown.

Function Description
IsDigit True if Value is a positive integer, an empty string, or a string which contains only the characters 0 through 9. Other characters such as the following are not allowed: spaces, tabs, plus signs, minus signs, decimal points, hexadecimal digits, and the 0x prefix.
IsXDigit Hexadecimal digit: Same as IsDigit except the characters A through F (uppercase or lowercase) are also allowed. A prefix of 0x is tolerated if present.
IsAlpha

True if Value is a string and is empty or contains only alphabetic characters. False if there are any digits, spaces, tabs, punctuation, or other non-alphabetic characters anywhere in the string. For example, if Value contains a space followed by a letter, it is not considered to be alpha.

By default, only ASCII letters are considered. To instead perform the check according to the rules of the current user's locale, use IsAlpha(Value, "Locale").
IsUpper

True if Value is a string and is empty or contains only uppercase characters. False if there are any digits, spaces, tabs, punctuation, or other non-uppercase characters anywhere in the string.

By default, only ASCII letters are considered. To instead perform the check according to the rules of the current user's locale, use IsUpper(Value, "Locale").
IsLower

True if Value is a string and is empty or contains only lowercase characters. False if there are any digits, spaces, tabs, punctuation, or other non-lowercase characters anywhere in the string.

By default, only ASCII letters are considered. To instead perform the check according to the rules of the current user's locale, use IsLower(Value, "Locale").
IsAlnum Same as IsAlpha except that integers and characters 0 through 9 are also allowed.
IsSpace True if Value is a string and is empty or contains only whitespace consisting of the following characters: space (A_Space or `s), tab (A_Tab or `t), linefeed (`n), return (`r), vertical tab (`v), and formfeed (`f).
IsTime

True if Value is a valid date-time stamp, which can be all or just the leading part of the YYYYMMDDHH24MISS format. For example, a 4-digit string such as 2004 is considered valid. Use StrLen to determine whether additional time components are present.

Value must have an even number of digits between 4 and 14 (inclusive) to be considered valid.

Years less than 1601 are not considered valid because the operating system generally does not support them. The maximum year considered valid is 9999.

Remarks

Since literal numbers such as 128, 0x7F and 1.0 are converted to pure numbers before the script begins executing, the format of the literal number is lost. To avoid confusion, the string functions listed above throw an exception if they are given a pure number.

A_YYYY, FileGetTime, If, StrLen, InStr, StrUpper, DateAdd

Examples

Checks whether var is a floating point number or an integer and checks whether it is a valid timestamp.

if isFloat(var)
    MsgBox var " is a floating point number."
else if isInteger(var)
    MsgBox var " is an integer."
if isTime(var)
    MsgBox var " is also a valid date-time."