Mayor Bloomberg pledged yesterday to combat widespread illegal parking by city employees in Chinatown and near City Hall."The city tries to enforce the laws and if somebody has a placard that permits them to park legally—in legal spaces—they should do it," he said. "And if not, we will take appropriate action."Bloomberg's vow followed a Daily News story about a study by Transportation Alternatives that showed, during one hour on March 29, 115 cars illegally parked on sidewalks and pedestrian areas.The lion's share of the illegally parked cars—some of which blocked hydrants—had city-issued placards that permit free parking in legal spots.Paul White, executive director of Transportation Alternatives, said he hopes the mayor's promise means the NYPD will "go above and beyond" what the department has done so far to address the problem."If 'appropriate action' means that they will start enforcing the law, then, we're in favor of that and we applaud the news," White said. "But if enforcing the law means business as usual then we can only say we'll continue to fight."