StringIsDigit Does not work properly

[Muhammad_Awais_Sharif]

Why this code does not work ?

$tmp = "1111"
If StringIsDigit($tmp) == True Then
    MsgBox(0,"",StringIsDigit($tmp) == "1")
EndIf

and this one works 

$tmp = "1111"
If StringIsDigit($tmp) == "1" Then
    MsgBox(0,"",StringIsDigit($tmp) == "1")
EndIf

 

[AndyG]

https://www.autoitscript.com/autoit3/docs/functions/StringIsDigit.htm

Reading the help helps

[Muhammad_Awais_Sharif]

1 minute ago, AndyG said:

https://www.autoitscript.com/autoit3/docs/functions/StringIsDigit.htm

Reading the help helps

Success: 1 does not mean True ?

what is wrong in comparing with true ?

[orbs]

the reason is you using the == operator, which is dedicated to case-sensitive string comparison, for boolean and numeric comparison, not cool.

[Muhammad_Awais_Sharif]

okay thank you 

[AndyG]

"1" is a string, and 1 is a number, TRUE is boolean....

you should not compare a string with a number ! The result of a comparison is TRUE or FALSE

(1 = "1") is (should be) FALSE   //EDIT (but NOT in AutoIt because of datatype "variant"?! ) so (1="1") in AutoIt is TRUE

(1 = TRUE) is TRUE

Edited September 27, 2016 by AndyG

[Muhammad_Awais_Sharif]

okay  

problem is that in C++ or java single = operator assign value.

So that's why i was using double equal

i got it ty  

[jchd]

More precisely, when you write:

If StringIsDigit($tmp) == True Then

the interpretor understands:

If '1' == 'True' Then

because == forces the conversion of its operands to strings and StringIsDigit returns the integer 0 or 1 (1 in your case), while the string 'True' stays by itself. Since the == comparison is over verbatim (case-insensitive) strings, it clearly fails.

The lazy, simple and robust way to code that condition is:

If StringIsDigit($tmp) Then

Edited September 27, 2016 by jchd

[bloopie]

3 hours ago, jchd said:

 

The lazy, simple and robust way to code that condition is:

If StringIsDigit($tmp) Then

 

 

 

 

Indeed!

@Muhammad_Awais_Sharif  ...Use a single equals (=) for comarison, as well as assignment in AutoIt for cases like this...or just say "If X Then" (whenever X is true..."Then" will execute)

(...It took me a few minutes to wrap my head around the 'single equals comparison' as well, so you're in good company!)

bloopie

Edited September 27, 2016 by bloopie
clarification