1. Create a <public> element as a child of the <component> element.

2. In the <public> element, include a <property> element that specifies the variable used to store property value.

3. To initialize the value of a simple property, create a global variable in the <script> element with a name matching propertyName (or propertyVariable, if you specified that) and assign it a value.

4. The following script component fragment illustrates two properties (name and tag) exposed as simple values. The properties are initialized using global variables in the <script> element.

   Note
   A CDATA section is required to make the script in the <script> element opaque. For details, see Script Component Files and XML Conformance.

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   <public> <property name="name"/> <property name="tag" internalName="tagVar"/> </public> <script language="VBScript"> <![CDATA[ Dim name name = "script component" ' Initializes the value of name property. Dim tagVar tagVar = "10" ' Initializes the value of tag property. ]]> </script>

1. In the script component file's <public> element, include a <property> element that contains a <get> element to define the read function and a <put> element to define the write function. If you do not include the <put> element, the property will be read-only. If you do not include the <get> element, the property will be write-only.

2. Write procedures in a <script> element outside the <public> element to implement the functions. The function for setting the property's value — the put function — must accept a single parameter, the value to set the property to.

   The names of the procedures must match the internal names you specified in the <property> element. If you did not specify an internalName attribute, the names of the functions must be the name of the function with the get_ prefix for a read function, and with a put_ prefix for the write function.

3. For example, the following script component fragment is an example of a script component file that exposes three properties: sname, dateOfBirth, and age. The dateOfBirth property is defined by functions so it can include error checking. The age property is calculated, and is therefore defined as read-only.

   Note
   A CDATA section is required to make the script in the <script> element opaque. For details, see Script Component Files and XML Conformance.

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   <public> <property name="sname"/> <property name="age"> <get internalName="readAge"/> </property> <property name="dateOfBirth"> <get internalName="readDOB"/> <put internalName="writeDOB"/> </property> </public> <script language="VBScript"> <![CDATA[ Dim sname ' Read-write sname property (no functions). Dim gDOB ' Global variable used to store date of birth. Function readDOB() ' Gets value of dateOfBirth property. readDOB = gDOB End Function Function writeDOB(newDOB) ' Sets value of dateOfBirth property. If isDate(gDOB) Then 'Error checking gDOB = newDOB End If End Function Function readAge() ' Calculates read-only age property. If isDate(gDOB) Then dobM = DatePart("m", gDOB) dobD = DatePart("d", gDOB) dobY = DatePart("yyyy", gDOB) todayY = DatePart("yyyy", Date) age = todayY - dobY ' Adjust if birthday has not yet occurred this year. bday = DateValue(dobM & "/" & dobD & "/" & todayY) If DateDiff("d", bday, DateValue(Date)) < 0 Then age = age - 1 End If readAge = age End If End Function ]]> </script>

You can specify a default property for a script component so the host application can get or set the property's value without explicitly naming the property. For example, if you have exposed a property called sname and marked it as the default, you can work with it in either of these ways in Visual Basic:

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Set component = CreateObject("Component.MyComponent") n = component.sname ' Gets property explicitly. n = component ' Gets value of sname as default.

To specify a default property, include an attribute assigning a special dispatch identifier (a dispid) to the method. For more information about dispids, see Exposing Events.

• In the <property> element, include the attribute dispid="0", as in the following example:

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  <property name="sname" dispid="0"/>

  Note
  This technique can be used to assign either a default property or a default method, but not both. There can be only one element in the script component with the dispid of zero.