javascript - 调用函数时如何设置if条件

Question

点击按钮调用函数显示div mac_1，然后点击运行按钮点击函数调用三次，如何通过div id设置if条件

$("#run").click(function() {$('#resultFrame').contents().find('html').html("<style>" + $('#css').val() + "</style>" + $("#html").val());
    document.getElementById('resultFrame').contentWindow.eval($('#js').val());
        else if 
        {
            $('#resultFrame1').contents().find('html').html("<style>" + $('#css').val() + "</style>" + $("#html").val());
    document.getElementById('resultFrame').contentWindow.eval($('#js').val());
        }
        else
    {
        $('#resultFrame3').contents().find('html').html("<style>" + $('#css').val() + "</style>" + $("#html").val());
    document.getElementById('resultFrame').contentWindow.eval($('#js').val());

点击按钮调用div

<div  class="mac_1"  id="mac_1" >
            <iframe id="resultFrame" height="100%" width="100%">
                <p>Your browser does not support iframes.</p>
            </iframe>
        </div>
        <div  class="ipad_1" id="ipad_1" style=" display: none;">
            <iframe id="resultFrame1" height="100%" width="100%">
                <p>Your browser does not support iframes.</p>
            </iframe>
        </div>
        <div  class="mob_1" id="mob_1" style=" display: none;">
            <iframe id="resultFrame3" height="100%" width="100%">
                <p>Your browser does not support iframes.</p>
            </iframe>
        </div>

Answer 1

那应该行得通。也许 capturePhoto() 有错误？插入 alert() 或 console.log():

if ( photo=="yes" )
{
  alert("Thank you StackOverflow, you're a very big gift for all programmers!");
  capturePhoto();
}
else
{
  alert("StackOverflow.com must help me!");
}

DEMO