for (var i = 0; i < increment.length; i++) { increment[i].index = i; increment[i].onclick = function() { var flag = this.index; var q = quantity[flag]; var p = price[flag].textContent; var s = subtotal[flag]; var newvalue = parseInt(q.value) + 1; q.setAttribute("value", newvalue); s.textContent = (newvalue * parseFloat(p)).toFixed(2); calculateTotal(); }; } //点减,小计 for (var j = 0; j < decrement.length; j++) { decrement[j].index = j; decrement[j].onclick = function() { var flag = this.index; var q = quantity[flag]; var p = price[flag].textContent; var s = subtotal[flag]; if (parseInt(q.value) > 0 ) { var newvalue = parseInt(q.value) - 1; q.setAttribute("value", newvalue); s.textContent = (newvalue * parseFloat(p)).toFixed(2); calculateTotal(); } }; } function calculateTotal() { var total = 0.0; for (var k = 0; k < subtotal.length; k++) { total += parseFloat(subtotal[k].textContent); } document.getElementById("total").textContent = total.toFixed(2); }根据此代码设置未点击时小计subtotal和总价total为0.00
时间: 2024-02-10 14:06:12 浏览: 26
您可以在代码中添加以下内容来设置未点击时小计subtotal和总价total为0.00:
```javascript
// 在页面加载时将小计和总价设置为0.00
window.onload = function() {
for (var k = 0; k < subtotal.length; k++) {
subtotal[k].textContent = "0.00";
}
document.getElementById("total").textContent = "0.00";
};
```
这段代码将在页面加载时运行,将所有的小计设置为0.00,并将总价设置为0.00,以确保在用户还没有开始点击加减按钮时,小计和总价都是0.00。
相关问题
for (var i = 0; i < a.length;i++)
This for loop is missing an increment statement for the variable i. It should be:
for (var i = 0; i < a.length; i++)
The increment statement (i++) will ensure that the loop continues to run until the condition (i < a.length) is no longer true.
//点加,小计 for (var i = 0; i < increment.length; i++) { increment[i].index = i; increment[i].onclick = function() { var flag = this.index; var q = quantity[flag]; var p = price[flag].textContent; var s = subtotal[flag]; var newvalue = parseInt(q.value) + 1; q.setAttribute("value", newvalue); s.textContent = (newvalue * parseFloat(p)).toFixed(2); calculateTotal(); }; } //点减,小计 for (var j = 0; j < decrement.length; j++) { decrement[j].index = j; decrement[j].onclick = function() { var flag = this.index; var q = quantity[flag]; var p = price[flag].textContent; var s = subtotal[flag]; if (parseInt(q.value) > 1) { var newvalue = parseInt(q.value) - 1; q.setAttribute("value", newvalue); s.textContent = (newvalue * parseFloat(p)).toFixed(2); calculateTotal(); } }; }根据此代码不点击按钮前设商品小计为一个商品的价格
如果不点击按钮,商品小计应该为商品单价乘以初始数量,可以在JavaScript代码中先获取每个商品的单价和数量输入框的初始值,然后计算商品小计,例如:
```javascript
var price = document.getElementsByClassName("price");
var quantity = document.getElementsByClassName("quantity");
var subtotal = document.getElementsByClassName("subtotal");
for (var i = 0; i < price.length; i++) {
var p = price[i].textContent;
var q = quantity[i].value;
var s = subtotal[i];
s.textContent = (q * parseFloat(p)).toFixed(2);
}
calculateTotal(); // 计算总价
```
这样就可以在页面加载时根据每个商品的单价和初始数量计算出商品小计。