Question

I found this example to make range work with switch statement:

function GetText(value)
{
    var result;

    switch (true)
    {
        case ((value >= 26) && (value <= 50)):
            result = ">= 26.";
            break;

        case ((value >= 1) && (value <= 25)):
            result = "Between 1 and 25.";
            break;

        case (value == 0):
            result = "Equals Zero.";
            break;

    }

    return result;
}

But if I modify the code and remove the second check for the value the example will still work:

function GetText(value)
{
    var result;

    switch (true)
    {
        case ((value >= 26)):
            result = ">= 26 .";
            break;

        case ((value >= 1)):
            result = "Between 1 and 25.";
            break;

        case (value == 0):
            result = "Equals Zero.";
            break;

    }

    return result;
}

So if I passed 29 even that I have two true cases the first one will be selected. My question is that how switch statement works in most of programming languages it will start comparing from the top or its only in this case (and is it good or bad to write it like that?).

Answer 1

switch statement checks for matches from top to bottom.

From MDN docs on switch statement:

If a match is found, the program executes the associated statements. If multiple cases match the provided value, the first case that matches is selected, even if the cases are not equal to each other.