遗漏的类型错误:无法设置的未定义的属性“值” - JS
问题描述:
好家伙,一个人可以帮我如何解决这个问题?我试图找出它3个小时,但仍然无法修复。它在事件的第一次尝试或第一次射击中工作,但如果事件再次触发,则不再有效。
这是剧本。
<script type="text/javascript" language="Javascript">
var sum=0;
function OnChange(value){
price = document.getElementById('select1').value;
quantity = document.getElementById('select2').value;
sum = price * quantity;
document.frmOne.txtDisplay.value = sum;
}
</script>
<SCRIPT language=Javascript>
<!--
function isNumberKey(evt)
{
var charCode = (evt.which) ? evt.which : event.keyCode
if (charCode > 31 && (charCode < 48 || charCode > 57))
return false;
return true;
}
//-->
</SCRIPT>
这里的FORM
<form NAME = "frmOne" action="initiateorder.php" method="post" enctype="multipart/form-data">
<input type="hidden" name="transnum" value="<?php echo $_GET['trnasnum'] ?>" />
<INPUT TYPE = "Text" name = "select1" size = "35" id="select1" value ="<?php echo $price ?>" style="display:none;">
<INPUT TYPE = "Text" name = "pname" size = "35" value ="<?php echo $name ?>" style="display:none;">
<br>
<span style="font-size:11px; font-family:Arial, Helvetica, sans-serif; text-align:left; line-height:17px;color:#000000;">Quantity : </span>
<input type="text" name="select2" id="select2" onkeyup="OnChange(this.value)" onKeyPress="return isNumberKey(event)" style="width:60px;" />
<span style="color:#B80000; font-size:16px; font-weight:bold; font-family:Arial, Helvetica, sans-serif;">=</span>
<INPUT TYPE = "Text" name = "txtDisplay" size = "35" value ="<?php echo $price ?>" style="border:#999999 solid 1px; background-color:#FFF; width:100px; height:20px;" readonly>
</form>
答
尝试document.getElementsByName("txtDisplay")[0].value = sum
代替document.frmOne.txtDisplay.value = sum;
为什么会变成这样的工作时,后者将无法正常工作? – Adam
它的工作!你能解释为什么吗? – nethken