How to check if current user has a specific security role in Dynamic CRM

vjCity.CleanseId = function (id) 

{

    return id.replace("{", "").replace("}", "");

}

vjCity.CurrentUserHasRole = function (roleName) 

{

    var userId = Xrm.Page.context.getUserId();

    return vjCity.HasRoleByName(roleName, userId);

}

vjCity.HasRoleByName = function (roleName, userId) 

{

    ///

    ///     Determines whether user has role.

    ///

    /// Name of the role.

    /// The user identifier.

    /// true if user has role otherwise false. 

    var roles = vjCity.GetUserRoles(true, userId);

    for (var i = 0; i < roles.length; i++) {

        if (roles[i].Name === roleName) {

            return true;

        }

    }

    return false;

}

vjCity.GetUserRoles = function (useCachedRole, userId) 

{

    ///

    ///     Gets the user roles.

    ///

    /// The use cached role(boolean).

    /// The user identifier. 

    userId = vjCity.CleanseId(userId);

    if (!useCachedRole || cachedUserRole[userId] == null) {

        var userRoles = [];

        var data = vjCity.GetEntitiesByCriteria('systemuserrolescollection', "?$select=roleid&$filter=systemuserid eq " + userId);

        if (data != null && data.value.length > 0) {

            for (var i = 0; i < data.value.length; i++) {

                var roleId = data.value[i].roleid;

                var name = vjCity.GetEntityById(roleId, "roles", "?$select=name").name;

                if (name != null) {

                    var role = {};

                    role.RoleId = vjCity.CleanseId(roleId);

                    role.Name = name;

                    userRoles.push(role);

                }

            }

            cachedUserRole[userId] = userRoles;

        }

    }

    return cachedUserRole[userId];

}

vjCity.GetEntityById = function (entityId, entityPlurarName, query) 

{

    entityId = vjCity.CleanseId(entityId);

    var data = null;

    var req = new XMLHttpRequest();

    req.open('GET', vjCity.GetWebAPIUrl() + entityPlurarName + "(" + entityId + ")" + query, false);

    req.setRequestHeader("Accept", "application/json");

    req.setRequestHeader("OData-MaxVersion", "4.0");

    req.setRequestHeader("OData-Version", "4.0");

    req.setRequestHeader("Prefer", "odata.include-annotations=*");

    req.send();

    if (req.readyState == 4 /* complete */) {

        if (req.status == 200) {

            data = JSON.parse(req.response);

        }

        else {

            var error = JSON.parse(req.response).error;

            console.log(error.message);

        }

    }

    return data;

}

vjCity.GetEntitiesByCriteria = function (entityPlurarName, query) 

{

    var data = null;

    var req = new XMLHttpRequest();

    req.open('GET', vjCity.GetWebAPIUrl() + entityPlurarName + query, false);

    req.setRequestHeader("Accept", "application/json");

    req.setRequestHeader("Content-type", "application/json; charset=utf-8");

    req.setRequestHeader("OData-MaxVersion", "4.0");

    req.setRequestHeader("OData-Version", "4.0");

    req.send();

    if (req.readyState == 4) {

        if (req.status == 200) {

            data = JSON.parse(req.response);

        }

        else {

            var error = JSON.parse(req.response).error;

            console.log(error.message);

        }

    }

    return data

}