LUA determines whether a variable is numeric, whether a string can be converted to a number, and so on

Source: Internet
Author: User
Tags numeric lua prepare

This article mainly introduces LUA to determine whether a variable is a numeric character, whether a string can be converted to a number, and so on, this article explains the Lua judgment is a character or a number of methods, LUA to determine the number of methods, to determine whether the conversion to the number of methods, judge and prepare a method of initial value, the need for friends can refer to the

One, Lua judgment is a character or a number

The code is as follows:

--If a variable is to be judged

Local T = type (x);

If T = = "number" Then

--it's a number.

else if T = = "string" Then

--is a string


If a judge is a string, to determine whether it can be turned into a number, the

Local n = tonumber (x);

If N Then

--N is to get the numbers


--Turn the number failure, not the number, then n = = Nil


Second, LUA judgment number

To determine an explicit

Type can determine which types have been converted, but it distinguishes the string because it looks at the original type.

Copy code code as follows:

>a= "12"

>print (Type (a))



1. Determination of the possibility of conversion

The direct use of the transformation to test can determine whether to turn to that type, that is, whether the type of string pattern.

The code is as follows:

> Print (Tonumber ("222"))


> Print (Tonumber ("222a"))



Judge and prepare an initial value

The code is as follows:

Srcstr=tonumber ("2323224a") or 1--nil will overflow, but will get 1

Print ("Transfer number" ...). SRCSTR)

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