innerHTML问题

Question

 document.getElementById(arrMustFill[i]).innerHTML+="<font color='#FF0000'>*必填</font>";这句话可以在指定位置加上*必填两个字，有没有办法能我已经有<font color='#FF0000'>*必填</font>这句了，我现在要用js将它代替了，比如将<font color='#FF0000'>*必填</font>换成<font color="red"></font>，让*必填不显示在

Answer 1

意思就是我现在html代码中有<font color='#FF0000'>*必填 </font>"这句，我要通过js将这句更新了，让它变成<font></font>,就等于什么都不显示了

Answer 2

可以，你还可以这么写，
document.getElementById(arrMustFill[i]).innerHTML+=" <font color='red'> </font>"; 说明：innerHTML 属性设置或返回表格行的开始和结束标签之间的 HTML
比如 <div id="testtest">ADSF</div>
如果用document.getElementById("testtest").innerHTML+=" <font color='#FF0000'>*必填 </font>"; 
结果为<div id="testtest">ADSF <font color='#FF0000'>*必填 </font></div>如果用document.getElementById("testtest").innerHTML+=" <font color='red'> </font>"; 
结果为<div id="testtest">ADSF <font color='red'> </font></div>这里用的是innerHTML+= 所以就是原有的内容加上新添的内容 当前id标签的内容。    

Answer 3

可以这么实现，<font id="fon1">aaaaaa</font>然后js中触发一个事件，fon1.innerText=""就行拉

Answer 4

你们这些我都试过了，给你们看看我的代码吧
 function langchunlin(s){
  //window.location.reload();
   //alert("类型"+s);
  if (s=='audio'){
    var arrMustFill=Array("material_id","title","content_type","artist","album");//将必填的控件ID放入数组
    for(var i=0;i<arrMustFill.length;i++){
      document.getElementById(arrMustFill[i]).outerHTML+="<font color='#FF0000'>*必填</font>"
    }
    
  }
  else if(s=='ringtone'){
    var arrMustFill=Array("material_id","title","content_type","artist","album");
   for(var i=0;i<arrMustFill.length;i++){
      document.getElementById(arrMustFill[i]).outerHTML+="<font color='#FF0000'>*必填</font>"
    }
  }
  else if(s=='video'){
   var arrMustFill=Array("material_id","title","content_type","artist","description","image_url");
   for(var i=0;i<arrMustFill.length;i++){
      document.getElementById(arrMustFill[i]).outerHTML+="<font color='#FF0000'>*必填</font>"
    }
  }
  else if(s=='image'){
   var arrMustFill=Array("material_id","title","content_type","image_url");
   for(var i=0;i<arrMustFill.length;i++){
      document.getElementById(arrMustFill[i]).outerHTML+="<font color='#FF0000'>*必填</font>"
    }
  }
   else if(s=='game'){
   var arrMustFill=Array("material_id","title","content_type","image_url","description","developer","app_platform","service_id","price");
   for(var i=0;i<arrMustFill.length;i++){
      document.getElementById(arrMustFill[i]).outerHTML+="<font color='#FF0000'>*必填</font>"
    }
  }
  document.getElementById("content_type").value=s;

}
  
<table align="center" width="100%" style="display: block" border="1"
cellspacing="0" bordercolor="#000000">
<tr>
<td>
素材id:
<input type="text" size="50" id="material_id" name="material_id"
value="<%=material_id%>">
</td>
</tr>
<tr>
<td>
标题：
<input type="text" size="50" id="title" name="title"
value="<%=mp.getNAME()%>">
</td>
</tr>
<tr>
<td>
类型：
<select id="content_type" name="content_type" onchange="javascript:langchunlin(this.value);">
<option value="image">
图片
</option>
<option value="ringtone">
铃音
</option>
<option value="video">
视频
</option>
<option value="audio">
音乐
</option>
<option value="game">
游戏
</option>
</select>
</td>
</tr>
<tr>
<td>
image_url:
<input type="text" size="50" id="image_url" name="image_url"
value="http://218.206.70.172/<%=mp.getPREVFILE()%>">
</td>
</tr>
<tr>
<td>
artist:
<input type="text" size="50" id="artist" name="artist" value="">
</td>
</tr>
<tr>
<td>
album:
<input type="text" size="50" id="album" name="album" value="">
</td>
</tr>
<tr>
<td>
description:
<input type="text" size="50" id="description" name="description"
value="">
</td>
</tr>
<tr>
<td>
developer:
<input type="text" size="50" id="developer" name="developer"
value="">
</td>
</tr>
<tr>
<td>
app_platform:
<input type="text" size="50" id="app_platform" name="app_platform"
value="">
</td>
</tr>
<tr>
<td>
service_id:
<input type="text" size="50" id="service_id" name="service_id"
value="">
</td>
</tr>
<tr>
<td>
price:
<input type="text" size="50" id="price" name="price" value="">
</td>
</tr>
<tr>
<td>
<input type="button" value="提交" onclick="submits()">
</td>
</tr>
</table>
看其中的<select id="content_type" name="content_type" onchange="javascript:langchunlin(this.value);">当我选中其中的一个在后面加个
<font color='#FF0000'>*必填</font> 可现在有个问题不如我点图片了在title后面加*必填了，我在点音乐在title后面会在加个*必填，我只需要一个，该是图片必填的就显示*号，不该他必填得就不显示*号，之前我用过window.location.reload();每次之前刷新下，可这东西在别的浏览器就不好用了，你们可以拿这代码式下就明白了

Answer 5

解决办法:尝试用DIV将你要提示的内容放在里面,每次调用onchange事件时,就清空已保存的提示信息即可.eg.只做了前两个select选项演示给你看下
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<META NAME="Generator" CONTENT="EditPlus">
<META NAME="Author" CONTENT="">
<META NAME="Keywords" CONTENT="">
<META NAME="Description" CONTENT=""><SCRIPT LANGUAGE="JavaScript">
function langchunlin(s){
  //调用事件前清空原有保存信息
  var arr = Array("material_id","title");
 for(var i=0;i<arr.length;i++){
      document.getElementById(arr[i]).innerHTML="";
    }   


  if (s=='rington'){
    var arrMustFill=Array("material_id","title");//将必填的控件ID放入数组
    for(var i=0;i<arrMustFill.length;i++){
      document.getElementById(arrMustFill[i]).innerHTML="<font color='#FF0000'>*必填</font>";
    }    
  }else if(s=="image"){
 var arrMustFill=Array("material_id","title",'image_url');//将必填的控件ID放入数组
    for(var i=0;i<arrMustFill.length;i++){
      document.getElementById(arrMustFill[i]).innerHTML="<font color='#FF0000'>*必填</font>";
    }   
  }
  
    
}</SCRIPT>
</HEAD><BODY>
<table align="center" width="100%" style="display: block" border="1"
                cellspacing="0" bordercolor="#000000">
                <tr>
                    <td>
                        素材id:
                        <input type="text" size="50"
                            value="<%=material_id%>"><div id="material_id"></div>
                    </td>
                </tr>
                <tr>
                    <td>
                        标题：
                        <input type="text" size="50" 
                            value="<%=mp.getNAME()%>"><div id="title"></div>
                    </td>
                </tr>
                <tr>
                    <td>
                        类型：
                        <select id="content_type" name="content_type" onchange="javascript:langchunlin(this.value);">
<option value=""></option>
                            <option value="image">
                                图片
                            </option>
                            <option value="ringtone">
                                铃音
                            </option>
                            <option value="video">
                                视频
                            </option>
                            <option value="audio">
                                音乐
                            </option>
                            <option value="game">
                                游戏
                            </option>
                        </select>
                    </td>
                </tr>
                <tr>
                    <td>
                        image_url:
                        <input type="text" size="50" 
                            value="http://218.206.70.172/<%=mp.getPREVFILE()%>"><div id="image_url"></div>
                    </td>
                </tr>
                <tr>
                    <td>
                        artist:
                        <input type="text" size="50" id="artist" name="artist" value="">
                    </td>
                </tr>
                <tr>
                    <td>
                        album:
                        <input type="text" size="50" id="album" name="album" value="">
                    </td>
                </tr>
                <tr>
                    <td>
                        description:
                        <input type="text" size="50" id="description" name="description"
                            value="">
                    </td>
                </tr>
                <tr>
                    <td>
                        developer:
                        <input type="text" size="50" id="developer" name="developer"
                            value="">
                    </td>
                </tr>
                <tr>
                    <td>
                        app_platform:
                        <input type="text" size="50" id="app_platform" name="app_platform"
                            value="">
                    </td>
                </tr>
                <tr>
                    <td>
                        service_id:
                        <input type="text" size="50" id="service_id" name="service_id"
                            value="">
                    </td>
                </tr>
                <tr>
                    <td>
                        price:
                        <input type="text" size="50" id="price" name="price" value="">
                    </td>
                </tr>
                <tr>
                    <td>
                        <input type="button" value="提交" onclick="submits()">
                    </td>
                </tr>
            </table></BODY>
</HTML>