JavaScript将选定值保留在选项中
我有两个选择,“区段”选项被禁用,直到“等级”的值为7到10JavaScript将选定值保留在选项中,javascript,php,codeigniter,Javascript,Php,Codeigniter,我有两个选择,“区段”选项被禁用,直到“等级”的值为7到10 <div class="form-inline"> <label for="studgrade">Grade</label> <select class="form-control" onchange="changeGrade();" id="studgrade" name="studgrade"> <
<div class="form-inline">
<label for="studgrade">Grade</label>
<select class="form-control" onchange="changeGrade();" id="studgrade" name="studgrade">
<option value="6">6</option>
<option value="7">7</option>
<option value="8">8</option>
<option value="9">9</option>
<option value="10">10</option>
<option value="11">11</option>
</select>
<label for="studsection">Section</label>
<select class="form-control" id="studsection" name="studsection">
<option>7</option>
<option>8</option>
<option>9</option>
<option>10</option>
</select>
</div>
等级
6.
7.
8.
9
10
11
部分
7.
8.
9
10
但每次我单击7时,“grade”值就会返回到6,这会使“section”选项处于禁用状态
以下是脚本:
<script>
$(document).ready(function(){
var selectedgrade = document.getElementById("studgrade");
var newgrade = selectedgrade.options[selectedgrade.selectedIndex].value;
document.getElementById("studsection").disabled = true;
if(newgrade < 7 || newgrade > 10){
document.getElementById("studsection").disabled = true;
} else if(newgrade >= 7 && newgrade <= 10) {
document.getElementById("studsection").disabled = false;
}
});
</script>
<script type="text/javascript">
function changeGrade() {
//var selectedgrade = $grade.options[$grade.selectedIndex].value;
var selectedgrade = document.getElementById("studgrade");
document.getElementById("studgrade").value = selectedgrade;
window.location.href = "<?php echo base_url().'schoolportal/addstudent'?>";
}
</script>
$(文档).ready(函数(){
var selectedgrade=document.getElementById(“studgrade”);
var newgrade=selectedgrade.options[selectedgrade.selectedIndex].value;
document.getElementById(“studsection”).disabled=true;
如果(新等级<7 | |新等级>10){
document.getElementById(“studsection”).disabled=true;
}否则,如果(newgrade>=7&&newgrade我自己已经弄明白了,我试图将条件语句放在方法changeGrade()中。我不明白。在您的change grade函数中,您重定向了用户。您希望复选框如何更新?问题在于您的changeGrade()
function-应该是document.getElementById(“studgrade”).value=selectedgrade.value;
因为selectedgrade
是一个对象。