Highlight the search text - angular 2

Question

A messenger displays the search results based on the input given by the user. Need to highlight the word that is been searched, while displaying the result. These are the h

Answer 1

The selected answer has the following issues:

1. It will return undefined if there is nothing provided in the search string
2. The search should be case insensitive but that should not replace the original string case.

i would suggest the following code instead

transform(value: string, args: string): any {
    if (args && value) {
        let startIndex = value.toLowerCase().indexOf(args.toLowerCase());
        if (startIndex != -1) {
            let endLength = args.length;
            let matchingString = value.substr(startIndex, endLength);
            return value.replace(matchingString, "" + matchingString + "");
        }

    }
    return value;
}