Microsoft® Visual Basic® Scripting Edition A Simple VBScript Page |
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With Microsoft Internet Explorer 3.0, you can view the page produced by the HTML code below. If you click the button on the page, you see VBScript in action.
The result is a little underwhelming: you see a dialog box with a phrase in it (Latin for "Wonderful to behold"). However, there's quite a bit going on.<HTML> <HEAD><TITLE>A Simple First Page</TITLE> <SCRIPT LANGUAGE="VBScript"> <!-- Sub Button1_OnClick MsgBox "Mirabile visu." End Sub --> </SCRIPT> </HEAD> <BODY> <H3>A Simple First Page</H3><HR> <FORM><INPUT NAME="Button1" TYPE="BUTTON" VALUE="Click Here"></FORM> </BODY> </HTML>When Internet Explorer reads the page, it finds the <SCRIPT> tags, recognizes there is a piece of VBScript code, and saves the code. When you click the button, Internet Explorer makes the connection between the button and the code, and runs the procedure.
The Sub procedure in the <SCRIPT> tags is known as an event procedure. You'll notice that there are two parts to the procedure name: the name of the button, Button1 (from the NAME attribute in the <INPUT> tag), and an event name, OnClick; the two names are joined by an underscore. Any time the button is clicked, Internet Explorer looks for and runs the corresponding event procedure, Button1_OnClick.
Internet Explorer 3.0 defines the events available for form controls in the Scripting Object Model documentation.
Pages can use combinations of controls and procedures, too. The next page, VBScript and Forms, shows some simple interactions between controls.
You can attach VBScript code to events in two other ways, although the preceding way is probably the simplest and most general.Internet Explorer 3.0 allows you to add short sections of inline code in the tag defining the control. For example, the following <INPUT> tag performs precisely the same action as the previous code example when you click the button:
Notice that the function call itself is enclosed in single quotation marks, and the string for the MsgBox function is enclosed in double quotation marks. You can use multiple statements as long as you separate the statements with colons (:).<INPUT NAME="Button1" TYPE="BUTTON" VALUE="Click Here" OnClick='MsgBox "Mirabile visu."'>You can also write a <SCRIPT> tag so that it applies only to a particular event for a specific control:
Because the <SCRIPT> tag already specifies the event and the control, you don't use the Sub and End Sub statements.<SCRIPT LANGUAGE="VBScript" EVENT="OnClick" FOR="Button1"> <!-- MsgBox "Mirabile visu." --> </SCRIPT>