Extend A Regular Expression To Negative Number

I want to extend the following regex to negative numbers. this.value = this.value.replace(/[^0-9\.]/g, ''); I tried adding minus sign doing something like this, (/[^-0-9.]/g, '')

Solution 1:

Uh, replacing every non-number character makes that a bit harder - it's like "negating" the regex. What I came up with is a negative lookahead, preventing a minus - which would be matched by [^0-9.] - from beeing matched if it is in the beginning of the string (using a start anchor):

….replace(/(?!^-)[^0-9.]/g, "")

Solution 2:

Why RegEx? How about:

var temp = parseFloat(this.value)
this.value = isNaN(temp) ? "" : temp;

This should also work:

var temp = +this.value;
this.value = isNaN(temp) ? "" : temp;

Solution 3:

Put your dash outside of the character class:

this.value = this.value.replace(/^-?[^0-9\.]/g, "");

Solution 4:

The regex in provided by you is faulty for the positive numbers itself as it will convert "100+200=300" to "100200300".

I suggest you try this: someString.match(/-?[\d]+.?[\d]*/);

Solution 5:

It is only to put the negative symbol in front of the 0

this.value = this.value.replace(/[^-0-9\.]/g, "");