通过类名称计算输入字段

Question

Here is my form:

<INPUT TYPE=TEXT NAME="input1" SIZE=10>
<INPUT TYPE=TEXT NAME="input2" SIZE=10>
<INPUT TYPE="button" VALUE="+" name="add"
onclick="CalculateIMSUB(this.form)">
<INPUT TYPE=TEXT NAME="Answer" SIZE=12>

Here is my function:

function CalculateIMSUB(form) {
var Atext = form.input1.value;
var Btext = form.input2.value;
var val = form.val.value;
var A = eval(Atext);
var B = eval(Btext);    
var answer = A - B;
form.Answer.value = answer;
}

Here is my question: I want my function to operate through classname. So, if my form were to look like this instead:

<INPUT TYPE=TEXT classNAME="input1" name="baboon" SIZE=10>
<INPUT TYPE=TEXT classNAME="input2" name="gorilla" SIZE=10>
<INPUT TYPE="button" VALUE="+" name="add"
onclick="CalculateIMSUB(this.form)">
<INPUT TYPE=TEXT NAME="Answer" SIZE=12>

The calculater function would still work. Many thanks

Answer 1

而不是使用id代替类，您可以使用document.getElementById（'ID'）。value引用它们，我认为有一个document.getElementByClass，但并非所有浏览器都完全支持

Answer 2

You could use the following to retrieve the element:

function CalculateIMSUB(form) {
var Atext = form.getElementById('input1').value;
var Btext = form.getElementById('input2').value;
var val = form.val.value;
var A = eval(Atext);
var B = eval(Btext);    
var answer = A - B;
form.Answer.value = answer;
}

for the following HTML:

<INPUT TYPE=TEXT id="input1" name="baboon" SIZE=10>
<INPUT TYPE=TEXT id="input2" name="gorilla" SIZE=10>
<INPUT TYPE="button" VALUE="+" name="add"
onclick="CalculateIMSUB(this.form)">
<INPUT TYPE=TEXT NAME="Answer" SIZE=12>

Answer 3

function getElementsByClassName(oElm, strTagName, strClassName){
    var arrElements = (strTagName == "*" && oElm.all)? oElm.all :
        oElm.getElementsByTagName(strTagName);
    var arrReturnElements = new Array();
    strClassName = strClassName.replace(/\-/g, "\\-");
    var oRegExp = new RegExp("(^|\\s)" + strClassName + "(\\s|$)");
    var oElement;
    for(var i=0; i < arrElements.length; i++){
        oElement = arrElements[i];
        if(oRegExp.test(oElement.className)){
            arrReturnElements.push(oElement);
        }
    }
    return (arrReturnElements)
}