Android Question sizeof(x) equivalent b4a

[MbedAndroid]

already searched forum, but how to determin a size of array or type in B4a?
For random acess i need to forward the point to a offset i*sizeof(y) where i is the pointer to the stored location and y and var which holds the type of vars

 

[TheJinJ]

Is this what your after? Apologies if not...

Dim myArray(10) As List
Log(myArray.Length)

 

[MbedAndroid]

doesnt work
i need to know the sizeof spots

Type SPOTSLABELS  (spotname As String,  positie As Position, Date As String, Time As String)
Dim Spots As SPOTSLABELS
/[code]
spots.length doesnt work

 

[TheJinJ]

Could you use

Spots.spotname.Length

 

[MbedAndroid]

it works for 1 var inside the type
i could make a adding of all the var's inside the type, that should work, but there must be a much easier way, only i dont know the equivalent in basic or b4a basic
Normally in #c you say sizeof(array) etc

 

[TheJinJ]

EDIT...not any use...I think you need to manually calculate the size of the array

 

[stevel05]

A Type is actually a class, the variables it holds are available by reference.

If you explain what you are trying to achieve it may be possible to get the result in different ways.

 

[MbedAndroid]

tried, compiler error for type

 

[MbedAndroid]

someone asked it before https://www.b4x.com/android/forum/threads/determine-size-of-typed-variables.14479/
the way is to add all length of fields

 

[MbedAndroid]

A Type is actually a class, the variables it holds are available by reference.

If you explain what you are trying to achieve it may be possible to get the result in different ways.

i'm saving several files, random each of type "spots" To index the pointer i need to know the size of "spots". I found this manually (304 bytes) so the application is working

the best way is to count each var inside the type like Erel mentioned in his answer. Basic doesnt seem to have a equivalent command of sizeof in C#

 

[stevel05]

If the Type holds non string variables then the length would be dependent on the value of the variable value, if the values are numeric, you could cast them to a string and measure their length but if they are boolean or another class or type then it would be more complicated.

 

[MbedAndroid]

one way is to set the length much larger then the actual size of type. Then the file contains blocks where the type will fit. This works, but not a nice way...

 

[Erel]

Two options:
1. Add all the type instances to a List and save the list with WriteB4XObject. You can then load the list and work with it.
2. Use KeyValueStore class.

 

[Yalçın Kondur]

I'm not sure if an equvalent of Delphi's SizeOf(TRecord) command exists in B4A.

Edit: Where did Delphi come to my mind?

 

[DonManfred]

Normally in #c you say sizeof(array) etc

Right. but you are not defining a array! You have definied just a single variable (a customtype).

 

[DonManfred]

You can use a list instead of a customtype. You then can get the lists length.

 

[MbedAndroid]

You can use a list instead of a customtype. You then can get the lists length.

Size AsInt [read only]
Returns the number of items in the list.
size only returns the number of items, not the total size in bytes

I'm not sure if an equvalent of Delphi's SizeOf(TRecord) command exists in B4A.

Edit: Where did Delphi come to my mind?

if Erel should release a C#4a i would buy it right away....