const HtmlEscapeMode({String name: "custom", bool escapeLtGt: false, bool escapeQuot: false, bool escapeApos: false, bool escapeSlash: false })

Create a custom escaping mode.

All modes escape &. The mode can further be set to escape < and > (escapeLtGt), " (escapeQuot), ' (escapeApos), and/or / (escapeSlash).

Source 

const HtmlEscapeMode(
    {String name: "custom",
    this.escapeLtGt: false,
    this.escapeQuot: false,
    this.escapeApos: false,
    this.escapeSlash: false})
    : _name = name;