在JavaScript中正确使用try / catch块

Question

I have a try/catch block that I have written into the JetBrains Webstorm IDE that is giving me an error. The error reads as follows: "'throw' of exception caught locally / This inspection reports any instances of JavaScript throw statements whose exceptions are always caught by containing try statements. Using throw statements as a 'goto' to change the local flow of control is likely to be confusing."

try {
    var invoice = parseInt(localStorage[0]);
    if (isNaN(invoice)) {
        console.warn("invoice NaN; let's fix that...");
        throw "executing catch";
    }
}
catch (e) {
    console.log(e);
    this.test();
    invoice = 1;
}
finally {
    localStorage[invoice] = JSON.stringify(Ticket);
    console.log("localStorage[" + invoice + '] : ' + localStorage[invoice]);
    localStorage[0] = parseInt(localStorage[0]) + 1;
}

If I place the activity from the catch block into the if block of the try block, then i will have no need of try/catch/finally. So how else would you throw an error other than with a conditional statement (if), and how can you avoid using throw as a "goto"?

Thanks!

Answer 1

This functions identically and is much cleaner. Why throw/catch?

try {
    var invoice = parseInt(localStorage[0]);
    if(isNaN(invoice)){
        console.warn("invoice NaN; let's fix that...");
        console.log("executing catch");   // not really needed
        this.test();
        invoice = 1;
    }
} finally {
    localStorage[invoice] = JSON.stringify(Ticket);
    console.log("localStorage[" + invoice + '] : ' + localStorage[invoice]);
    localStorage[0] = parseInt(localStorage[0]) + 1;
}