Retrieve dynamically added textbox read only value
===

I am working on a project where I render controls from loading information from a SQL table (includes control ID, validation, width and control type) I am working on some conditional formatting at the moment and i'm stuck on one thing - below is a code summary of what I am trying to achieve.

    Dim txtTimeAtAddress as new Textbox()
    txtTimeAtAddress.Attributes.Add("onchange", "IsLessThan(this,'PrevAddress1,PrevAddress2,PrevAddress3', 4, True)

I pass the condition control (Time at addreess) and a comma seperated string of controls to action, the value that the condition should be less than and then whether or not to enable the action control if the condition is met.

		function IsLessThan(condtion, action, iValue, readonly) {
			var iConditionValue = TryParseInt(condtion.value, null);
			var Array = action.split(",");
			if (iConditionValue == null) {
				for (var i = 0; i < Array.length; i++) {
					var v1 = FindTableControl(Array[i]);
					v1.readOnly = !(readonly);
					if (v1.readOnly) {
						v1.value = "";
					}
				}
			} else if (iConditionValue < iValue) {
				for (var j = 0; j < Array.length; j++) {
					var v2 = FindTableControl(Array[j]);
					v2.readOnly = !(readonly);
					if (v2.readOnly) {
						v2.value = "";
					}
				}
			} else {
				for (var k = 0; k < Array.length; k++) {
					var v3 = FindTableControl(Array[k]);
					v3.readOnly = readonly;
					if (v3.readOnly) {
						v3.value = "";
					}
				}
			}
		}

When I reference txtTimeAtAddress.ReadOnly it always returns false, i've tried .Attributes("readOnly") and this also doesn't work so i'm wondering how I will get this value in my code behind?