Overview
This page has advanced features that require a knowledge of JavaScript.
Details
In expressions (created by using Expression dialog or using <%= %> syntax in the template) the following short-hand is allowed to reference variable values:
<%= #code %> results in the variable's value or blank if the value is null.
<%= #code1 + #code2 %> if the values are numeric, will result in the two numbers being added together, otherwise the two values will be concatenated together.
In expressions, script, or script blocks
| Variable Type | Missing value treated as null | Missing value included | Variables without a missing value definition |
|---|---|---|---|
| Numeric | #code.displayValue.value | #code.value.value | |
| Numeric calculation | |||
Categorical value (e.g. 0, 1) (radio button or picklist) | #code.displayValue.value | #code.value.value | |
Categorical name (eg. no, yes) (radio button or picklist) | #code.displayValue.name | #code.value.name | |
| Date | To display a date: #code.displayValue.toString() To use a date in a calculation: #code.value.value | ||
| Text / memo | #code.displayValue.toString() | ||
| Checkbox | #code.value.value |
#code.displayValue.toString() displays:
- The variable's value, or
- Blank if the value is null or defined as a missing value
#code.value.toString() displays:
- the variable's value (even if the value is defined as missing) or
- blank if the value is null.
#code.displayValue.value displays:
- Numeric variables: returns a number
- Date variables: returns a date
- All other variables: returns a string representation of the value
- Missing values or null: returns null
#code.value.value displays:
- Numeric variables: returns a number
- Date variables: returns a date
- All other variables: returns a string representation of the value
- Missing values: returns the missing value
- Null: returns null
#code.value.value - if the value is for a numeric variable, the result is a number; if the value is for a date variable, the result is a date; otherwise the result is a string representation of the value. If the value is null, the result is null. Note, values defined as missing are returned (i.e., they are not returned as null).
#code.displayValue.name - returns the picklist display name associated with the variable's value. If the value is null or defined as a missing value, empty string is returned.
#code.value.name - returns the picklist display name associated with the variable's value even if the value is defined as missing. If the value is null, empty string is returned.
Detailed explanation
#code - refers to an object with the following properties: variableId, definition, displayValue, value.
1) variableId: Integer key of the variable (used as input to some methods on the Encounters collection).
2) definition: an object that has properties and method:
a) name: variable name.
b) description: variable description.
3) displayValue and value return an object with the following properties. The object returned for displayValue treats values defined as missing as being null.
a) name: picklist display name associated with the variable or empty string if null.
b) value: the variable's value as the variable's type. Thus, numeric values are returned as number or NaN if null; date values are returned as Date objects or null; and other other data is returned as a string. If the value is null, null is returned so statement like "if (#code == null)" will be true if the value is null.
c) IsNull: returns true if the value is null.
d) toString(): returns a string representation of the value or empty string.
Examples
Output a variable value:
<% Output.Write( #code.displayValue.toString() );
Output a variable value even if it is defined as missing:
<% Output.Write( #code.value.toString() );
Output a sum of two numeric variables:
<% Output.Write( #code1.displayValue.value == null || #code2.displayValue.value == null ? '' : #code1.displayValue.value + #code2.displayValue.value ) %>