I recommend reading the String section in the thread posted by fysiks.
Accessing a string within an array of strings and accessing a sub-string can look identical. It all depends on how the variable is defined.
Referencing a string with a supplied index ( Var1[ X ] ) can mean either:
1. You want to reference a full string within an array of strings
-- Works if the var is defined as Var1[ 33 ][ 50 ]
2. You want to access a sub-string within a single string.
-- Works if the var is defined as Var1[ 33 ]
Since you are specifying 'id' as your index I assume you are trying to store data on a per-player basis. To solve your problem, create an array of strings so each player has his own string to store info.
PHP Code:
new Var1[ 33 ][ 35 ]
//copy users name to the string array element 'id'
get_user_name( id , Var1[ id ] , charsmax( Var1[] ) );
client_print( [...] , "hello %s" , Var1[ id ] );
//copy "hello there" to the string array element 'id'
copy( Var1[ id ] , charsmax( Var1[] ) , "hello there" );
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