Question

I have a large number of text fields that need to be evaluated onkeyup to be sure nothing is entered but numbers. Decimals are ok. So is the absence of a value.

For some reason this is matching on decimals. Eg I type 4 and then . and it flags on .

How do I correct this?

var s_in = 0;
for (var i = 10; i < 19; i++) {
    var fObj = document.getElementById(field+'_'+i);
    var text = fObj.value;
    if (text) {
        var s = parseInt(text);
        var pattern = /^[+-]?(\d*\.)?\d+$/;
        var result;
        if ((result = pattern.exec(text)) != null) {
            if (s > -1) {
                s_in += s;
            }
        } else {  // not empty and not a number
            alert('The entry for Hole ' + i + ' ' + ucfirst(field) + ' is "' + text + '" This is not a number. It will be erased now.');
            fObj.value = '';
            fObj.focus();
            return false;
        }
    }
}

Answer 1

Your regex requires one or more digits after the decimal point and you have to escape the - in the first group). If you don’t want to require a digit after the decimal, then you can use this (changes a + to a * and puts \ in front of the -):

/^[+\-]?(\d*\.)?\d*$/