Javascript If Statement不会运行

Question

if语句不会运行.我想知道是否有人能发现问题,因为我不能.

var a=parseFloat(document.form2.mark1.value);
var b=parseFloat(document.form2.mark2.value);
var c=parseFloat(document.form2.mark3.value);

var total2=(a+b);
if (total2 < 70) 
{ 
    document.form2.realmark.value= "You Have received a Passed";
}
else if(total2 < 89)
{
    document.form2.realmark.value= "You Have received a Ultra passed";
}
else if(total2 < 100)
{
    document.form2.realmark.value= "You Have received Passed Insane";
}
else
{
    window.alert("broken");
}

我通过一个按钮来调用它,如果我没有if语句,它就可以工作.

<input name="button4" id="button4" type="button" value="Calculate Overal Mark" onClick="getmark2()" />
<br /><br />
<b>Overall Mark:</b>
<input name="realmark" type="text" id="realmark" size="35" readonly="readonly" />

它甚至不会window.alert("broken");在底部运行.

Answer 1

这正是你告诉它要做的事情.

total2被设置为100,但所有的if语句被编程的时候才执行total2是小于 100.