MACROMEDIA COLDFUSION MX 61-DEVELOPING COLDFUSION MX, Руководство по разработке

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112 Chapter 5: Using Arrays and Structures
Populating an array from a query
When populating an array from a query, keep the following things in mind:
•
You cannot add query data to an array all at once. A looping structure is generally required to
populate an array from a query.
•
You can reference query column data using array-like syntax. For example,
myquery.col_name[1] references data in the first row in the col_name column of the myquery
query.
•
Inside a
cfloop query=
loop, you do not have to specify the query name to reference the
query’s variables.
You can use a
cfset
tag with the following syntax to define values for array indexes:
<cfset arrayName [ index ]= queryColumn [ row ]>
In the following example, a
cfloop
tag places four columns of data from a sample data source
into an array, myarray.
<!--- Do the query --->
<cfquery name="test" datasource="cfsnippets">
SELECT Emp_ID, LastName, FirstName, Email
FROM Employees
</cfquery>
<!--- Declare the array --->
<cfset myarray=arraynew(2)>
<!--- Populate the array row by row --->
<cfloop query="test">
<cfset myarray[CurrentRow][1]=Emp_ID>
<cfset myarray[CurrentRow][2]=LastName>
<cfset myarray[CurrentRow][3]=FirstName>
<cfset myarray[CurrentRow][4]=Email>
</cfloop>
<!--- Now, create a loop to output the array contents --->
<cfset total_records=test.recordcount>
<cfloop index="Counter" from=1 to="#Total_Records#">
<cfoutput>
ID: #MyArray[Counter][1]#,
LASTNAME: #MyArray[Counter][2]#,
FIRSTNAME: #MyArray[Counter][3]#,
EMAIL: #MyArray[Counter][4]# <br>
</cfoutput>
</cfloop>
This example uses the query object built-in variable CurrentRow to index the first dimension of
the array.