jquery if else语句不起作用

I am checking the variable wal, which I get from a PHP file with json_encode. If wal's value is under 100, it should render a calendar where selectable = false. Else, it should render a calendar where selectable = true.

My code looks like this (fullCalendar is not included in this snippet):

$(document).ready(function () {
    if (wal < "100") {
        alert (wal);
        var calendar = $('#calendar').fullCalendar(
        {
            selectable: false,
        }
    });

    } else {
        alert (wal); 
        var calendar = $('#calendar').fullCalendar(
        {
            selectable: true,}
        });   
    };
}

In one case, war = 120, so it should fire the else condition, but it still renders selectable = false.

Where is my mistake?

Edit 1

I changed if (wal < 100) to if (parseInt(wal) < 100). With wal = 120, it jumps into the else statement. But if I change war to a lower number (like wal = 60) it still jumps into the else statement, bypassing the first statement.

if (wal < "100") 

should be changed to

if (parseInt(wal, 10) < 100) 

to properly compare numbers data types.