javascript 如何使文件上传字段成为必填字段
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How to make file upload field mandatory
提问by user3367831
Hello can anyone plz fix this problem.
你好任何人都可以解决这个问题。
my input field is below code and I am doing validation on form submit i.eis:
我的输入字段在代码下方，我正在对表单提交 i.eis 进行验证：
<input name="file[]" type="file" multiple="multiple">
<form name="bdmrequest" enctype="multipart/form-data" method="post" action="<?php echo $_SERVER["PHP_SELF"];?>" onsubmit="return(validate());">
i have included validate.js in header and i am able to do validation of other fields except file upload. validation code i am using:
我在标题中包含了 validate.js 并且我能够验证除文件上传之外的其他字段。我正在使用的验证代码：
if(document.bdmrequest.file.value== "")
{
alert("Attachment Required");
document.bdmrequest.file.focus();
return false;
}
js doesn't support me to use (document.bdmrequest.file[].value== "") please suggest me the alternatives. the name of my input type has to be file[] only.
js 不支持我使用 (document.bdmrequest.file[].value== "") 请给我建议替代方案。我的输入类型的名称只能是 file[]。
回答by Shaunak D
If you need pure Javascript: Demo Fiddle
如果您需要纯 Javascript：演示小提琴
function validate(){
var inp = document.getElementById('upload');
if(inp.files.length === 0){
alert("Attachment Required");
inp.focus();
return false;
}
}
jQuery:
jQuery：
function validate(){
if($('#upload')[0].files.length === 0){
alert("Attachment Required");
$('#upload').focus();
return false;
}
}
回答by Dileep Kumar
No need of JavaScript validation you can use "required" attribute in input type....
无需 JavaScript 验证，您可以在输入类型中使用“required”属性....
<input type="file" required="required">
回答by Alex Char
You can check if the value is empty.
您可以检查该值是否为空。
<input name="file[]" type="file" multiple="multiple" id="uploadField">
And then in js:
然后在js中：
if($("#uploadField").val() != ""){
//your success code here
}
