LiveDocs Comments - coldfusion - 7 - htmldocs - 00000960.htm

coldfusion/7/htmldocs/00000960.htm

halL — 2007-07-20T08:32:34

This is not an official Adobe response, but my personal observation:
I'd be careful about using all-numeric structure key names.
As a general rule, ColdFusion correctly converts between numeric values and their string representations.
Therefore, you can use an-all numeric structure key because it is really a string of numeric characters.
However, doing so results in the "interesting" behaviors that Ashish-Saxena points out.

coldfusion/7/htmldocs/00000960.htm

halL — 2007-07-20T08:04:02

Here is full working code based on Ahsish-Saxena's sample.

myStruct=StructNew();
myStruct.type = "key";
mystruct.key1 = 1;
myStruct.key2[1] = 3;
myStruct["key3"]["struct2key2"] = 5;
myStruct.key2[mystruct.key1 + mystruct.key1] = 9;
myStruct["key"& myStruct.key2[2]]["struct2key2"] = 5;
myStruct[ myStruct.type & myStruct.key2[2]]["struct2key2"] = 5;

coldfusion/7/htmldocs/00000960.htm

Ashish-Saxena — 2007-07-20T03:57:54

Key names can be derived by combinations of variables:
I am adding a line of code in above code of structure

See the last two lines of code and its output:

myStruct.type = key
mystruct.key1 = 1
myStruct.key2[2] = 3
myStruct["key3"]["struct2key2"] = 5
myStruct.key2[mystruct.key1 + mystruct.key1] = 3
myStruct["key"& myStruct.key2[2]]["struct2key2"] = 5
myStruct[ myStruct.type & myStruct.key2[2]]["struct2key2"] = 5

coldfusion/7/htmldocs/00000960.htm

Ashish-Saxena — 2007-07-20T03:22:58

We know "A structure's key must be a string.", but structure's key name (not key value) may be a numeric also for example if array index (with in a structure) is using as structure key, following scenior may be possible:

Note the line of code

Key: "#key#" is

"a Numeric"

"Not a Numeric"

Output:
Key: "STRUCT2KEY1" is "Not a Numeric"
Key: "22" is "a Numeric"
Key: "STRUCT2KEY2" is "Not a Numeric"

There may be following two cases:
If structure key name(not its value) is of type numeric then remember following points:
(1)With in square bracket[] :
(i) Numaric key name can be either enclosed in quote(single,double) or without quote,but other keys must be in quote otherwise gives Error.
(ii)With in square bracket, other key levels may be in array or object property notation.
myStruct.key3[22] = Value22
myStruct.key3["22"] = Value22
myStruct.key3['22'] = Value22
myStruct["key3"]["22"] = Value22
ERROR :(If Key3 is not in quote.) Variable KEY3 is undefined. myStruct[key3]["22"]
(2)Not in square bracket[] :
(1)Only the dot(object property) notation (in all levels) is used.
ERROR- myStruct["key3"].22
myStruct.key3.22 = Value22
(3)Use built in function StructFind().
StructFind(myStruct.key3,"22") = Value22

If array index is using as structure key(i.e. numeric key, not value of key):
(1)With in square bracket[] :
(i) Numaric(Indexed) key name can be either enclosed in quote(single,double) or without quote,but other keys must be in quote otherwise gives Error.
(ii)With in square bracket, other key levels may be in array or object property notation.
myStruct.key2[2] = 3
myStruct.key2["2"] = 3
myStruct.key2['2'] = 3
myStruct["key2"]['2'] = 3
ERROR :(If key2 is not in quote.) Variable KEY2 is undefined.myStruct[key2]['2']
(2)Not in square bracket[] :
Neither array nor dot notation can be used.
ERROR :myStruct.key2.2
ERROR :myStruct["key2"].2
(3)Cannot use built in function StructFind().
Both lines give error
You have attempted to dereference a scalar variable of type class coldfusion.runtime.Array as a structure with members.
ERROR :StructFind(myStruct.key2,2)
ERROR :StructFind(myStruct.key2,"2")