CODEWITHSUNDEEP
algorithmarrayssearchcoldfusionstruct
Joshua Carmody
Joshua Carmody

Reputation: 13730

ColdFusion - What's an efficient way to search an array of structs?

I have a semi-large (hundreds of records) 1-dimensional array in ColdFusion. Each item in the array is a struct with several properties. I want to search the array for a struct that has a specific "name" property. I know that for an array of string values I could use Java methods like so:

<cfset arrayIndex = myArray.indexOf("WhatImLookingFor") + 1>

...but that won't work for an array of structs. I also know I could brute-force it like this:

<cfset arrayIndex = 0>
<cfloop from="1" to="#ArrayLen(myArray)#" index="counter">
    <cfif myArray[counter].name IS "WhatImLookingFor">
        <cfset arrayIndex = counter>
    </cfif>
</cfloop>

...but I feel like there must be a more efficient way. Does anyone have a better solution than this? You can assume that the "name" property is present in every struct and there are no gaps or other objects in the array.

Upvotes: 15

Views: 15029

Answers (5)

Organiccat
Organiccat

Reputation: 5651

You either want to use StructFindValue or StructFindKey

https://helpx.adobe.com/coldfusion/cfml-reference/coldfusion-functions/functions-s/structfindvalue.html

https://helpx.adobe.com/coldfusion/cfml-reference/coldfusion-functions/functions-s/structfindkey.html

Upvotes: 0

Russ
Russ

Reputation: 1951

In CF 10 or Railo 4, you can use:

arrayIndex = ArrayFind(arrayOfStructs, function(struct){ 
   return struct.name == "WhatImLookingFor"; 
});

It is not documented, but it works! ArrayFindAll() is also an option if you want all of the indices.

Upvotes: 10

Soldarnal
Soldarnal

Reputation: 7778

Unless you have a hash table you're creating as you build the array, I don't see how you're going to create a search function that is faster than the O(n) solution you've posted. Anyway, while you are building your arrays, you could do something like this:

<cfloop query="qryValues">
    <cfset nameValues[name] = currentrow />
    <cfset myArray[currentrow].name = name />
</cfloop>

<cfset arrayIndex = nameValues["WhatImLookingFor"] />

This assumes that the value always exists. You may need to check StructKeyExists(nameValues, "WhatImLookingFor") before making the call.

Upvotes: 12

Henry
Henry

Reputation: 32905

CFGroovy FTW! :)

<cfset count = 0>
<g:script>
count = myArray.find({ 
  it["NAME"] == "WhatImLookingFor" }
})
</g:script>

or.. if you like a more java style (w/o closure)

<cfset count = 0>
<g:script>
for (i in myArray) {
  if( i["NAME"] == "WhatImLookingFor" )
    count++
}
</g:script>

Upvotes: 0

Jas Panesar
Jas Panesar

Reputation: 6639

Without looking at it too deeply, I would consider converting the structure to a query (below) and then doing do a query of a query.. assuming your dataset isn't too huge!

http://www.bennadel.com/blog/264-Ask-Ben-Converting-A-Struct-To-A-Query-And-More-Java-.htm

Do share what you ended up doing!

Edit: The StructFindValue suggested looks to be excellent as well, I didn't think to look up any relevant functions.

Upvotes: 1

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