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Introduction |   |
JavaScript is an object-oriented, interpreted language, written for a virtual computer, e.g. a never-builded computer, emulated by internet browsers. Its files read/write possibilities are reduced, except with activeX objects. A clic on sample, will show you how JavaScript (and php) may collect informations about your system... None of these informations are transmitted on Internet. You may get the message "Some softwares (ActiveX controls) on this page may be unsafe. Would you autorize their execution ?" It's safe FOR THIS PAGE, and you need to answer yes to see the whole sample ... You may obtain an error message when opening the page, saying that "An ActiveX object couldnot have been created", due to high-level security parameters on your system, or network. Furthermore, a part of the sample can run only on Microsoft systems (ActiveX), but the rest run with others systems too. Here's some other scripts:
JavaScript is made of comments and instructions associated together. An instruction can include standard or user-defined functions, variables, datas (strings, numbers, ...) , and expressions. Comments It's ALWAYS necessary to comment your code, at least to could read it again after 6 months...
Comments begins by /* and ends by */, like this: /* After the tenth rewriting, a well-commented code is always better! */ Instructions Instructions include one or several elements and symbols on a line ended by ';', used as ending charachter. aText = "Hello!"; var myVar = 2 + 2; Blocks An instructions group inside {} is called a block. Blocks are used in functions definition and in conditionnal expressions. function SayHelloTo(MrSmith) { Alert("Hello, " + MrSmith); }
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