使用@Responsebody注解并且返回值类型为String时，返回的string字符串带有双引号

2023-04-18 21:31:40

当请求服务或前端页面的字符串出现："“字符串中有双引号”"

直接原因：controller返回时，springmvc直接将string类型转成了json字符串，应该在json解析器之前添加字符串解析器

解决
解决办法：配置字符串解析器org.springframework.http.converter.StringHttpMessageConverter

@EnableWebMvc
@Configuration
public class WebDataConvertConfig implements WebMvcConfigurer {

    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        StringHttpMessageConverter stringHttpMessageConverter = new StringHttpMessageConverter(StandardCharsets.UTF_8);
        converters.add(stringHttpMessageConverter);
 }

遇到的坑

springboot中配置了将返回前端的Long型数据转换为String类型，结果直接返回前端String类型数据时，出现字符串含双引号【实际是个json字符串】

@EnableWebMvc
@Configuration
public class WebDataConvertConfig implements WebMvcConfigurer {

    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        MappingJackson2HttpMessageConverter jackson2HttpMessageConverter = new MappingJackson2HttpMessageConverter();
        ObjectMapper objectMapper = new ObjectMapper();
        /**
         * 	序列换成json时,将所有的long变成string
         * 	因为js中得数字类型不能包含所有的java long值
         */
        SimpleModule simpleModule = new SimpleModule();
        simpleModule.addSerializer(Long.class, ToStringSerializer.instance);
        simpleModule.addSerializer(Long.TYPE, ToStringSerializer.instance);
        objectMapper.registerModule(simpleModule);
        jackson2HttpMessageConverter.setObjectMapper(objectMapper);
        converters.add(jackson2HttpMessageConverter);
    }
}