Ellipsis in the middle of a text (Mac style)

Question

I need to implement ellipsis (\"...\") in the middle of a text within a resizable element. Here is what it might look like. So,

\"Lorem ipsum do         


        

Answer 1

Another stab:

function truncate( str, max, sep ) {
    max = max || 10;
    var len = str.length;
    if(len > max){
        sep = sep || "...";
        var seplen = sep.length;
        if(seplen > max) { return str.substr(len - max) }

        var n = -0.5 * (max - len - seplen);
        var center = len/2;
        return str.substr(0, center - n) + sep + str.substr(len - center + n);
    }
    return str;
}

console.log( truncate("123456789abcde") ); // 123...bcde (using built-in defaults) 
console.log( truncate("123456789abcde", 8) ); // 12...cde (max of 8 characters) 
console.log( truncate("123456789abcde", 12, "_") ); // 12345_9abcde (customize the separator)