javascript eval()

document.order.T1.value=document.order.Q1.value*document.order.P1.value;
document.order.T2.value=document.order.Q2.value*document.order.P2.value;
document.order.T3.value=document.order.Q3.value*document.order.P3.value;

等同

var form=document.order;
for (var i=1;i<=3;i++){

• eval('form.T'+i+'.value=form.Q'+i+'.value(form.P'+i+'.value');

}  




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