Java 编辑显示从数据库中选择的dropwdown值的Servlet

Java 编辑显示从数据库中选择的dropwdown值的Servlet,java,mysql,servlets,web-applications,drop-down-menu,Java,Mysql,Servlets,Web Applications,Drop Down Menu,我想显示选中的dropwdown值,这样管理员就可以编辑表单,而无需再次选择该值。我尝试了这段代码,但它不起作用,该值不显示所选的值,它需要管理员重新选择。是否有任何错误?你们谁能建议一些代码或修复我的 pw.println("<div class=\"form-group\">"); pw.println("<label class=\"control-label col-lg-2\">Employment Type <span class=\"r

我想显示选中的dropwdown值,这样管理员就可以编辑表单,而无需再次选择该值。我尝试了这段代码,但它不起作用,该值不显示所选的值,它需要管理员重新选择。是否有任何错误?你们谁能建议一些代码或修复我的

    pw.println("<div class=\"form-group\">");
    pw.println("<label class=\"control-label col-lg-2\">Employment Type <span class=\"required\">*</span></label>");
    pw.println("<div class=\"col-lg-10\">");
    pw.println("<select class=\"form-control m-bot15\" name=\"j_empType\" value='"+ j.getJobemptype() +"' required/> \n " +
    "<option value=\"\" selected disabled>Please Select...</option> \n " +
    "<option value=\"Permanent\">Permanent</option> \n " +
    "<option value=\"Contract\">Contract</option> \n " +
    "<option value=\"Temporary\">Temporary</option> \n " +
    "<option value=\"Part Time\">Part Time</option>");
    pw.println("</select>");
    pw.println("</div>");
    pw.println("</div>");
pw.println(“”);
pw.println(“就业类型*”);
pw.println(“”);
pw.println(“\n”+
“请选择…\n”+
“永久\n”+
“合同\n”+
“临时\n”+
“兼职”);
pw.println(“”);
pw.println(“”);
pw.println(“”);

我不明白你的代码,因为它有点未格式化,也没用。 我想你的意思是:

for(MyEnum e : MyEnum.values()){
      pw.println("<option value=\""+e.name()+"\">"e.name()"</option>");
}
for(MyEnum e:MyEnum.values()){
println(““e.name()”);
}

好的,终于拿到了哈哈哈

pw.println("<div class=\"form-group\">");
   pw.println("<label class=\"control-label col-lg-2\">Employment Type <span class=\"required\">*</span></label>");
   pw.println("<div class=\"col-lg-10\">");

   if(!"".equalsIgnoreCase(j.getJobemptype()) && j.getJobemptype()!=null){

        if(j.getJobemptype().equalsIgnoreCase("Permanent")){

            pw.println("<select class=\"form-control m-bot15\" name=\"j_empType\" value='"+ j.getJobemptype() +"' required/> \n " +
               "<option value='"+ j.getJobemptype() +"'>"+j.getJobemptype()+"</option>\n " +
               "<option value=\"Contract\">Contract</option> \n " +
               "<option value=\"Temporary\">Temporary</option> \n " +
               "<option value=\"Part Time\">Part Time</option>");
            pw.println("</select>");

        }else if(j.getJobemptype().equalsIgnoreCase("Contract")){

            pw.println("<select class=\"form-control m-bot15\" name=\"j_empType\" value='"+ j.getJobemptype() +"' required/> \n " +
               "<option value='"+ j.getJobemptype() +"'>"+j.getJobemptype()+"</option>\n " +
               "<option value=\"Permanent\">Permanent</option> \n " +
               "<option value=\"Temporary\">Temporary</option> \n " +
               "<option value=\"Part Time\">Part Time</option>");
            pw.println("</select>");
        }else if(j.getJobemptype().equalsIgnoreCase("Temporary")){

            pw.println("<select class=\"form-control m-bot15\" name=\"j_empType\" value='"+ j.getJobemptype() +"' required/> \n " +
               "<option value='"+ j.getJobemptype() +"'>"+j.getJobemptype()+"</option>\n " +
               "<option value=\"Permanent\">Permanent</option> \n " +
               "<option value=\"Contract\">Contract</option> \n " +
               "<option value=\"Part Time\">Part Time</option>");
            pw.println("</select>");

        }else if(j.getJobemptype().equalsIgnoreCase("Part Time")){

                            pw.println("<select class=\"form-control m-bot15\" name=\"j_empType\" value='"+ j.getJobemptype() +"' required/> \n " +
                              "<option value='"+ j.getJobemptype() +"'>"+j.getJobemptype()+"</option>\n " +
                              "<option value=\"Permanent\">Permanent</option> \n " +
                              "<option value=\"Contract\">Contract</option> \n " +
                              "<option value=\"Temporary\">Temporary</option>");
                            pw.println("</select>");

                            }
                              }else {
                                pw.println("<select class=\"form-control m-bot15\" name=\"j_empType\" value='"+ j.getJobemptype() +"' required/> \n " +
                                  "<option value=\"Permanent\">Permanent</option> \n " +
                                  "<option value=\"Contract\">Contract</option> \n " +
                                  "<option value=\"Temporary\">Temporary</option> \n " +
                                  "<option value=\"Part Time\">Part Time</option>");
                                pw.println("</select>");
                                  }
    pw.println("</div>");
    pw.println("</div>");
pw.println(“”);
pw.println(“就业类型*”);
pw.println(“”);
if(!“”.equalsIgnoreCase(j.getJobemptype())和&j.getJobemptype()!=null){
if(j.getJobemptype().equalsIgnoreCase(“永久”)){
pw.println(“\n”+
“+j.getJobemptype()+”\n”+
“合同\n”+
“临时\n”+
“兼职”);
pw.println(“”);
}else if(j.getJobemptype().equalsIgnoreCase(“合同”)){
pw.println(“\n”+
“+j.getJobemptype()+”\n”+
“永久\n”+
“临时\n”+
“兼职”);
pw.println(“”);
}else if(j.getJobemptype().equalsIgnoreCase(“临时”)){
pw.println(“\n”+
“+j.getJobemptype()+”\n”+
“永久\n”+
“合同\n”+
“兼职”);
pw.println(“”);
}else if(j.getJobemptype().equalsIgnoreCase(“兼职”)){
pw.println(“\n”+
“+j.getJobemptype()+”\n”+
“永久\n”+
“合同\n”+
“临时”);
pw.println(“”);
}
}否则{
pw.println(“\n”+
“永久\n”+
“合同\n”+
“临时\n”+
“兼职”);
pw.println(“”);
}
pw.println(“”);
pw.println(“”);

这就是我们希望用db值填充下拉列表值的方式,对吗?但如果这是第一个数据呢?那么值将不可用..:(