Application.cfc setting DSN and calling that DSN

问题

I have been shown how to do this with Application.cfc instead of using the Application.cfm - that is fine, I like learning new stuff. Yet after I made the change I cannot figure out how to get the DSN working properly. Before I just used a set DSN in the Application.cfm file.

<cfparam name="DSN" default="">
<cfset DSN = "krl" />

And called it out here:

<CFQUERY NAME="Inital" DATASOURCE="#DSN#">
    SELECT Website_Name
    FROM InitalizationData
</CFQUERY>

Now setting it like:

component {
    this.name = "app"; 
    this.Sessionmanagement = true;
    this.datasource = "krl";

    public void function onSessionStart() {
        // initialize cart 
        session.cart = [];
    }
}

How do I call it out in my queries?

回答1:

Inside Application.cfc, you would usually add a function onApplicationStart(). Then, inside that function define

application.dsn = "foo";

And reference it like so:

<cfquery name="test" datasource="#application.dsn#">

When you define the variable as this.datasource inside a CFC, the this scope exists only in the context of that CFC. It's not accessible from outside it.

回答2:

I am able to use this.datasource in any CFM page. Example:

<cfinsert tableName="#variables.type#s" dataSource="#this.datasource#">

Application.cfc looks something like this:

<cfcomponent
    displayname="Application"
    output="true"
    hint="Handle the application.">

    <!--- Set up the application. --->
    <cfset THIS.Name = "#cgi.server_name#" />
    <cfset THIS.SessionManagement = true />
    <cfset THIS.ApplicationTimeout = CreateTimeSpan( 1, 0, 0, 0 ) />
    <cfset THIS.SessionTimeout = CreateTimeSpan( 0, 0, 30, 0 ) />
    <cfset THIS.SetClientCookies = true />
    <!--- FOR THE DATASOURCE --->
    <cfset this.datasource = "MyDSN" />
...
</cfcomponent>

However in regular tags you don't need to specify the datasource at all, if it's in the THIS scope:

<cfquery name="get">
SELECT id
FROM restaurants
WHERE email = '#something#'
UNION       
SELECT id
FROM individuals
WHERE email = '#something#'
</cfquery>

来源：https://stackoverflow.com/questions/39002299/application-cfc-setting-dsn-and-calling-that-dsn

标签

coldfusion

application.cfc