SpringBoot返回Long型数据前端精度丢失问题处理

新建一个类，实现 WebMvcConfigurer 接口，重写 extendMessageConverters 方法，启动类上添加 @EnableAutoConfiguration 注解

import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.module.SimpleModule;
import com.fasterxml.jackson.databind.ser.std.ToStringSerializer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

import java.text.SimpleDateFormat;
import java.util.List;
import java.util.TimeZone;

@Configuration
public class WebMvcConfig implements WebMvcConfigurer {

    @Override
    public void extendMessageConverters(List<HttpMessageConverter<?>> converters) {
        converters.removeIf(MappingJackson2HttpMessageConverter.class::isInstance);
        converters.add(0, new MappingJackson2HttpMessageConverter(objectMapper()));
    }

    @Bean
    public ObjectMapper objectMapper() {
        ObjectMapper mapper = new ObjectMapper();

        //忽略未知属性
        mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);

        //日期格式转换
        mapper.setDateFormat(new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"));
        mapper.setTimeZone(TimeZone.getTimeZone("GMT+8"));

        //Long类型转String类型
        SimpleModule simpleModule = new SimpleModule();
        simpleModule.addSerializer(Long.class, ToStringSerializer.instance);
        simpleModule.addSerializer(Long.TYPE, ToStringSerializer.instance);
        mapper.registerModule(simpleModule);
        return mapper;
    }

}