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arrays_20of_20structures_20_28lbb_29 [2018/03/31 13:19] – external edit 127.0.0.1arrays_20of_20structures_20_28lbb_29 [2024/01/05 00:22] (current) – external edit 127.0.0.1
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 //by Richard Russell, December 2014//\\ \\  One of the language extensions provided by [[http://www.lbbooster.com/|LB Booster]] is native **arrays of structures**. These can be useful for structured data storage within a program, or when calling a Windows API function (for example [[http://msdn.microsoft.com/en-us/library/windows/desktop/dd162814.aspx|Polygon]]) which requires an array of structures as one of its parameters.\\ \\  The syntax for declaring an array of structures is very similar to that for declaring a single structure; the only difference is the addition of the dimension(s) in parentheses:\\  //by Richard Russell, December 2014//\\ \\  One of the language extensions provided by [[http://www.lbbooster.com/|LB Booster]] is native **arrays of structures**. These can be useful for structured data storage within a program, or when calling a Windows API function (for example [[http://msdn.microsoft.com/en-us/library/windows/desktop/dd162814.aspx|Polygon]]) which requires an array of structures as one of its parameters.\\ \\  The syntax for declaring an array of structures is very similar to that for declaring a single structure; the only difference is the addition of the dimension(s) in parentheses:\\ 
 +<code lb>
   STRUCT sname(dims), member1 AS type, member2 AS type...    STRUCT sname(dims), member1 AS type, member2 AS type... 
 +</code>
 Arrays of structures may have any number of dimensions, limited only by available memory. As with ordinary numeric and string arrays the index value runs from 0 to the specified maximum dimension.\\ \\  Accessing an individual member, in order to change or read its value, again uses a syntax very similar to that used for a single (scalar) structure:\\  Arrays of structures may have any number of dimensions, limited only by available memory. As with ordinary numeric and string arrays the index value runs from 0 to the specified maximum dimension.\\ \\  Accessing an individual member, in order to change or read its value, again uses a syntax very similar to that used for a single (scalar) structure:\\ 
 +<code lb>
   sname(index).member.struct = newvalue   sname(index).member.struct = newvalue
   PRINT sname(index).member.struct   PRINT sname(index).member.struct
 +</code>
 \\  To pass the entire array of structures as a parameter to an API function use the following syntax:\\  \\  To pass the entire array of structures as a parameter to an API function use the following syntax:\\ 
 +<code lb>
   sname() AS struct   sname() AS struct
 +</code>
 Note the use of a pair of parentheses with nothing in between.\\ \\  Here are a couple of examples of the use of arrays of structures. Firstly an adaptation of the program by Dennis McKinney at the [[http://lbpe.wikispaces.com/ArraysAndStructs|Lliberty BASIC Programmer's Encyclopedia]]:\\  Note the use of a pair of parentheses with nothing in between.\\ \\  Here are a couple of examples of the use of arrays of structures. Firstly an adaptation of the program by Dennis McKinney at the [[http://lbpe.wikispaces.com/ArraysAndStructs|Lliberty BASIC Programmer's Encyclopedia]]:\\ 
 +<code lb>
   'define array of 100 structures   'define array of 100 structures
        struct test(99),_        struct test(99),_
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   [quit]   [quit]
        end        end
 +</code>
 \\  Secondly, an example of passing an array of structures to an API function:\\  \\  Secondly, an example of passing an array of structures to an API function:\\ 
 +<code lb>
       nomainwin       nomainwin
       open "Structure array" for graphics as #w       open "Structure array" for graphics as #w
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       close #w       close #w
       end       end
 +</code>
arrays_20of_20structures_20_28lbb_29.1522502345.txt.gz · Last modified: 2024/01/05 00:18 (external edit)