The method for the numerical calculation of Feynman amplitudes developed in a previous paper is extended to the standard electroweak theory (Weinberg-Salam model). All possible types of vertices contained in this model are added in the program package. As an application, the tree-level cross section for the process e+e- --> W+W-gamma is calculated using the presented programs. Comparison of the results with those obtained by other methods is discussed in detail. From the integration of the squared amplitude over the phase space, the radiative correction of O(alpha) to the differential cross section is calculated.