there is no way to check MIME type on the client side, the best you can do is tofunction JudgeKeyword(aForm)
{
if (aForm.pic1name.value == "")
{
alert("请选择本地图片文件!");
aForm.pic1name.focus();
return (false);
}
else
{
var nPos = document.aForm.pic1name.value.lastIndexOf(".");
var bGood = false;
if (nPos >0)
{
var ext = document.aForm.pic1name.value.substring(nPos + 1).toLowerCase();
if (ext == "gif" || ext == "jpg" || ext == "jpeg")
bGood = true;
} if (!bGood)
{
alert("Please select gif/jpg files!");
return false;
}
}
return (true);
}
{
if (aForm.pic1name.value == "")
{
alert("请选择本地图片文件!");
aForm.pic1name.focus();
return (false);
}
else
{
var nPos = document.aForm.pic1name.value.lastIndexOf(".");
var bGood = false;
if (nPos >0)
{
var ext = document.aForm.pic1name.value.substring(nPos + 1).toLowerCase();
if (ext == "gif" || ext == "jpg" || ext == "jpeg")
bGood = true;
} if (!bGood)
{
alert("Please select gif/jpg files!");
return false;
}
}
return (true);
}
回复 | 推荐 | 收藏 | 专题 | 公告 | 管理 | 关闭窗口
主 题: 如何在submit时判断input type="file"中接收的文件的格式(gif,jpg等)
作 者: cnshell (蓬蓬)
等 级:
信 誉 值: 100
所属论坛: Javascript
问题点数: 20
回复次数: 0
发表时间: 2002-3-13 11:26:11
请看这段代码:
请帮我看一下JudgeKeyword段,我想判断接受的文件是GIF/JPG,JPEG等,否则不允许执行SUBMIT动作。 <script language="javascript">
function JudgeKeyword(aForm)
{
if (aForm.pic1name.value == "")
{
alert("请选择本地图片文件!");
aForm.pic1name.focus();
return (false);
}
if(((aForm.pic1name.value).toLowerCase()).indexOf("gif")==0 ||((aForm.pic1name.value).toLowerCase()).indexOf("jpg")==0 )
{
alert("格式不对")
return false}
return (true);
}
</script>
function JudgeKeyword(aForm)
{
if (aForm.pic1name.value == "")
{
alert("请选择本地图片文件!");
aForm.pic1name.focus();
return false;
}
if(!(((aForm.pic1name.value.toLowerCase()).indexOf(".gif") > 0) || ((aForm.pic1name.value.toLowerCase()).indexOf(".jpg") > 0 ) || ((aForm.pic1name.value.toLowerCase()).indexOf(".jpeg") > 0 )))
{
alert("格式不对")
return false
}
}
</script>
<form name=aForm>
<input type=file name=pic1name>
<input onclick=JudgeKeyword(aForm)
</form>