Accessing custom control variable in code behind

Hey All,

 I have created a custom control .aspx page and in this set a public string i.e testName

 In the .aspx page i can access this by going

 <custom control: testName ="blah" ...> etc

 But in the code behind when i load a control to my custom page

i.e

 Control test

test = mycontrol.aspx

and try and access the variables

test.testName it doesnt show up as a valid option...any ideas ?
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