Thymeleaf中input框的默认值设定

如下所示：

<span><input type="text" th:name="dbType" th:value="${tDbSource.dbType} == null ? 'MySQL5.1' : ${tDbSource.dbType}"/></span>

注意：这里不能用th:field属性，根据官方文档解释，th:field会被解析为th:name和th:value，因此，th:field只支持“${...}”或“*{...}”类型表达式

 ......${tDbSource.dbType}" is not valid: only variable expressions ${...} or selection expressions *{...} are allowed in Spring field bindings (template: "mvcdemo" - line 23, col 39)

这时若还要使用默认值，可以在对象的构造函数中或是初始化对象时设定默认值

 @GetMapping("/")
    public ModelAndView index(){
        tDbSource.setHostip("127.0.0.1");
        tDbSource.setDbType("MySQL5.1");
        ModelAndView modelAndView = new ModelAndView("mvcdemo");
        modelAndView.addObject("tDbSource",tDbSource);
        return modelAndView;
    }