The sample code you defined there won't trigger an exception since you're not calling the functions inside your try block, you are just defining them. Due to the nature of JScript's treatment of global objects, it won't check for the existence of
foo on declaration, since
foo could still be assigned later. Therefore, there's no real use in wrapping function declarations in try-catch blocks.
Perhaps the best way to implement custom exception handling for all your functions, is to wrap the code inside all your event handlers such as OnEvent_Initialize or OnChatWndEvent_Created.
Javascript code:
// Main event, wrapped in try-catch block
function OnEvent_Initialize() {
try {
DoThis();
DoThat();
} catch(error) {
MsgPlus.DisplayToast("Error!", error.description);
}
}
// Script functions calling each other
function DoThis() {
HelpMeWithThis();
CallingUnknownFunction(); // try-catch in main event catches this
}
function HelpMeWithThis() { ... }
function DoThat() { ... }
As you can see, despite being wrapped in other functions, the exception will still reach the try-catch block in the event handler. These are the starting points of your call stacks, so any exception occurring inside a function called from the event will bubble up in the call stack until it hits the try-catch block in your event handler code.
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