Javascript正则表达式组合

Question

var cost_price = "15..00"

/*Cost price should be such that it should contain numbers and may not contain more than one dot*/

if(/^([0-9])|([.])/.test(cost_price)){

    documet.write("Correct cost price");

}

现在尽管cost_price中有两个点我得到了问候消息。我应该在if条件下改变什么？

P.S。我结合了2 reg ex。一个检查数字是否正确，另一个检查点是否只出现一次。

Answer 1

为什么不去

/^[0-9]+(\.[0-9]+)?$/

因此最后一部分完全可选？ （?指定＆＃34; 匹配0到1次＆＃34;）

如果您想允许.15，您可以将第一个[0-9]+（匹配1到无穷大时间）更改为[0-9]*（匹配0到无穷大时间）。

Answer 2

正则表达式适用于您的情况：

/^\d+(\.\d+)?$/

Answer 3

var cost_price = "15..00"

if (/\d+\.\d+/.test(cost_price)) {
    documet.write("Correct cost price");
} else {
    documet.write("Incorrect cost price");
}

http://regex101.com/r/cL8pP1

<强>说明

Match a single digit 0..9 «\d+»
   Between one and unlimited times, as many times as possible, giving back as needed (greedy) «+»
Match the character “.” literally «\.»
Match a single digit 0..9 «\d+»
   Between one and unlimited times, as many times as possible, giving back as needed (greedy) «+»