Question

jsp下拉列表框默认显示查询的一条数据

比如jsp页面下拉菜单中有“一班”、“二班”、“三班”等选项，我从数据库查询的数据是“三班”，怎样在下拉菜单中默认显示“三班”

Answer 1

jsp下拉列表框默认显示查询的一条数据可以给select标签赋值，只取其中的一条数据即可。
import java.util.ArrayList;
import java.util.Iterator;
public class Test{

ArrayList list;

// constructor; builds some sample data.
public Test(){
this.list = new ArrayList();
this.list.add(new String[]{"1", "January"});
this.list.add(new String[]{"2", "February"});
this.list.add(new String[]{"3", "March"});
this.list.add(new String[]{"4", "April"});
this.list.add(new String[]{"5", "May"});
this.list.add(new String[]{"6", "June"});
this.list.add(new String[]{"7", "July"});
this.list.add(new String[]{"8", "August"});
this.list.add(new String[]{"9", "September"});
this.list.add(new String[]{"10", "October"});
this.list.add(new String[]{"11", "November"});
this.list.add(new String[]{"12", "December"});
}

[B]
/**
* @return The months of the year as HTML Option tags.
* @param The number of the selected month as a string.
*/
public String getMonthAsOptions(String selectedMonth){

StringBuffer sb = new StringBuffer();
for(Iterator i = this.list.iterator(); i.hasNext(); ){
String[] m = (String[])i.next();
String monthNumber = m[0];
String monthText = m[1];

sb.append("<option value=\"");
sb.append(monthNumber);
sb.append("\"");
if(monthNumber.equals(selectedMonth))
sb.append(" selected");
sb.append(">");
sb.append(monthText);
sb.append("</option>\n");
}
return sb.toString();
}
[/B]
// main method for testing and debugging only
public static void main(String[] args){
String selectedMonth = "4";
if(args.length > 0)
selectedMonth = args[0];

Test test = new Test();
System.out.println(test.getMonthAsOptions(selectedMonth));
}
}

Answer 2

/**假设查找出来的是其他资产
返回回来传到的参数是：message
**/
<select>
<%
if(message="其他资产")
out.println("<option selected='selected'>message</option>");
else
out.println("<<option >固定资产</option>");
%>

<select>

原理就是输出的结果在out.print的时候加个selected='selected'就可以了。楼主给分吧！！！！！

Answer 3

可以在<option>里用jstl 的el表达式判断来选择

Answer 4

<select>
<option>一班</option>
<option>二班</option>
<option selected="selected">三班</option>
</select>