$out = strlen($in) > 50 ? substr($in,0,50)."..." : $in;

or 

.ellipsis {
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
}

Add ... using css when string or title not fit on place
Add … if string is too long

Now, assuming the element has a fixed width, the browser will automatically break off and add the ... for you.

Add … if string is too long

CSS