jQuery Window Width else if statement

Question

I am wondering why my last else if statement never gets executed. I am trying to do this:

$(document).ready(function() {
    function checkWidth() {
        var windowSize = $(window).width();

        if (windowSize <= 479) {
            console.log("screen width is less than 480");
        }
        else if (windowSize = 480 && windowSize <= 719) {
            console.log("screen width is less than 720 but greater than or equal to 480");
        }
        else if (windowSize = 720 && windowSize <= 959) {
            console.log("screen width is less than 960 but greater than or equal to 720");
        }
        else if (windowSize >= 960) {
            console.log("screen width is greater than or equal to 960");
        }
    }

    // Execute on load
    checkWidth();
    // Bind event listener
    $(window).resize(checkWidth);
});​

Everything gets logged in the console except for the last else if. What am I doing wrong?

Thanks,

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Answer 1

You are missing a couple >= in your code, and windowSize is not being compared but assigned a new value as a result of statements like windowSize = 480. Try this version instead:

$(document).ready(function() {
    function checkWidth() {
        var windowSize = $(window).width();

        if (windowSize <= 479) {
            console.log("screen width is less than 480");
        }
        else if (windowSize <= 719) {
            console.log("screen width is less than 720 but greater than or equal to 480");
        }
        else if (windowSize <= 959) {
            console.log("screen width is less than 960 but greater than or equal to 720");
        }
        else if (windowSize >= 960) {
            console.log("screen width is greater than or equal to 960");
        }
    }

    // Execute on load
    checkWidth();
    // Bind event listener
    $(window).resize(checkWidth);
});​

Answer 2

You're missing a greater than sign :

else if (windowSize = 720

and using just the equal sign ?

Try this instead:

$(document).ready(function() {
    function checkWidth() {
        var windowSize = $(window).width();

        if (windowSize < 480) {
            console.log("screen width is less than 480");
        }
        else if (windowSize < 720) {
            console.log("screen width is less than 720 but greater than or equal to 480");
        }
        else if (windowSize < 960) {
            console.log("screen width is less than 960 but greater than or equal to 720");
        }
        else {
            console.log("screen width is greater than or equal to 960");
        }
    }

    // Execute on load
    checkWidth();
    // Bind event listener
    $(window).resize(checkWidth);
});​

FIDDLE