Javascript正则表达式-仅过滤整数字符串，也为负数

Question

I'm trying to create a regex validation of a string and I want to check if string is an integer string, positive or negative.

I tryed to create my expression and I'm able to filter only digit with symbol '-' but I can't match as true string that begin with '-' (optional) and contains any digit at the end.

This is my try:

    var intRegex = /^[-?\d]+$/g;

    console.log(intRegex.test('55')); // true
    console.log(intRegex.test('artgz')); // false
    console.log(intRegex.test('55.3')); // false
    console.log(intRegex.test('-55')); // true
    console.log(intRegex.test('--55')); // true but I don't want this true
    console.log(intRegex.test('5-5')); // true but I don't want this true

Any idea?

Answer 1

you can use /^-?\\d+$/ , you want hyphen(-) only 0 or 1 times, so you use ? after -, and \\d can be 1 or more times so use + for \\d only.

 var intRegex = /^[-]?\\d+$/g; console.log(intRegex.test('55')); // true console.log(intRegex.test('artgz')); // false console.log(intRegex.test('55.3')); // false console.log(intRegex.test('-55')); // true console.log(intRegex.test('--55')); // true but I don't want this true console.log(intRegex.test('5-5')); // true but I don't want this true