switch无效，总是执行 default：

Question

你可以输出document.form1.btype.value看看是什么再说

Answer 1

晕，解决了，原来是没有加入break：

Answer 2

语法错误：switch (czs) {
    case '3D':        break;
    case '2B':        break;
    default ：        break;
}

Answer 3

switch (czs) {
    case '3D':
        document.form1.award12.value='1000';
        document.form1.award22.value='';
        document.form1.award32.value='';
        document.form1.award42.value='';
        document.form1.award52.value='';
        document.form1.award62.value='';
        document.form1.award72.value='';
        break；
    case '2B':
        document.form1.award12.value='5,000,000';
        document.form1.award22.value='';
        document.form1.award32.value='3000';
        document.form1.award42.value='200';
        document.form1.award52.value='10';
        document.form1.award62.value='5';
        document.form1.award72.value='';
        break；
    case '367':
        document.form1.award12.value='';
        document.form1.award22.value='';
        document.form1.award32.value='';
        document.form1.award42.value='500';
        document.form1.award52.value='100';
        document.form1.award62.value='10';
        document.form1.award72.value='46';
        break；
    case '265':
        document.form1.award12.value='';
        document.form1.award22.value='50';
        document.form1.award32.value='';
        document.form1.award42.value='';
        document.form1.award52.value='';
        document.form1.award62.value='';
        document.form1.award72.value='';
        break；
    default:
        document.form1.award12.value='';
        document.form1.award22.value='';
        document.form1.award32.value='';
        document.form1.award42.value='';
        document.form1.award52.value='';
        document.form1.award62.value='';
        document.form1.award72.value='';
         break；
不加break；将匹配的case 开始执行，直到default，所以最后的结果是：
         document.form1.award12.value='';
        document.form1.award22.value='';
        document.form1.award32.value='';
        document.form1.award42.value='';
        document.form1.award52.value='';
        document.form1.award62.value='';
        document.form1.award72.value='';

Answer 4

switch (czs) {
    case '3D':
        document.form1.award12.value='1000';
        document.form1.award22.value='';
        document.form1.award32.value='';
        document.form1.award42.value='';
        document.form1.award52.value='';
        document.form1.award62.value='';
        document.form1.award72.value='';
        break；
    case '2B':
        document.form1.award12.value='5,000,000';
        document.form1.award22.value='';
        document.form1.award32.value='3000';
        document.form1.award42.value='200';
        document.form1.award52.value='10';
        document.form1.award62.value='5';
        document.form1.award72.value='';
        break；
    case '367':
        document.form1.award12.value='';
        document.form1.award22.value='';
        document.form1.award32.value='';
        document.form1.award42.value='500';
        document.form1.award52.value='100';
        document.form1.award62.value='10';
        document.form1.award72.value='46';
        break；
    case '265':
        document.form1.award12.value='';
        document.form1.award22.value='50';
        document.form1.award32.value='';
        document.form1.award42.value='';
        document.form1.award52.value='';
        document.form1.award62.value='';
        document.form1.award72.value='';
        break；
    default:
        document.form1.award12.value='';
        document.form1.award22.value='';
        document.form1.award32.value='';
        document.form1.award42.value='';
        document.form1.award52.value='';
        document.form1.award62.value='';
        document.form1.award72.value='';
         break；
不加break；将匹配的case 开始执行，直到default，所以最后的结果是：
         document.form1.award12.value='';
        document.form1.award22.value='';
        document.form1.award32.value='';
        document.form1.award42.value='';
        document.form1.award52.value='';
        document.form1.award62.value='';
        document.form1.award72.value='';

Answer 5

var czs=document.form1.btype.value;下拉菜单取值错误，所以没有对应值 就一直defalutvar obj=document.getElementById("btype");
var czs=obj.options[obj.selectedIndex].text;//用这两句取值