client.ClientCredentials.UserName.UserName = "myUserName";
client.ClientCredentials.UserName.Password = "myPassword";
string anything = client.getValue(@"anyParam..");

<basicHttpBinding>
    <binding name="ServiceNameHereServiceBinding" >
        <security mode="TransportCredentialOnly">
            <transport clientCredentialType="Basic" proxyCredentialType="None"
                    realm="">
            </transport>
        </security>
    </binding>
</basicHttpBinding>

// Assign client.ClientCredentials.UserName.UserName and client.ClientCredentials.UserName.Password
SetupClientAuthentication();

HttpRequestMessageProperty httpRequestProperty = new HttpRequestMessageProperty();

httpRequestProperty.Headers[HttpRequestHeader.Authorization] = "Basic " +
    Convert.ToBase64String(Encoding.ASCII.GetBytes(client.ClientCredentials.UserName.UserName + ":" +
    client.ClientCredentials.UserName.Password));

using (OperationContextScope scope = new OperationContextScope(client.InnerChannel))
{
    OperationContext.Current.OutgoingMessageProperties[HttpRequestMessageProperty.Name] =
        httpRequestProperty;

    // Invoke client
}