How to modify a RegEx to accept a + sign

[Claus Mygind]

The function below takes a string and highlights the text within the string that matches the search criteria. It works fine unless the user includes the + sign. Then this line
var re = new RegExp('(' + searchStr + ')', 'gi');
generates a "SyntaxError: invalid quantifier"

So obviously the + has to be escaped \+. Can that be added to the RegEx expression or does that have to be tested and inserted first?

function HighlightSearchValue(oObj, searchStr, addLineBreak)
{
    /*
    -------------------------------------------
    this function higlights the section of text
    which the user entered as a search criteria
    -------------------------------------------
    */
 
    var re  = new RegExp('(' + searchStr + ')', 'gi');
 
    var ret = oObj.split(re);
 
    for (var i = 0, l = ret.length; i < l; i++) {
        if (re.test(ret[i])) {
            ret[i] = ret[i].replace(re, '<span style="color:red;">' + ret[i] + '</span>');
        }
    }
    var result = ret.join('')+(( addLineBreak) ? '<br/>':'');
 
    return result;
 
}
 

[Dormilich]

Can that be added to the RegEx expression or does that have to be tested and inserted first?

if RegExp could mask their special characters, what would there be left from the RegExp?

So I guess you need to do it beforehand. splitting and re-joining the string seems like an easy way for it.

function escape_plus(str)
{
    return str.split('+').join('\\+');
}