Answer 1

如果你想使用jQuery的validate，你可以通过创建这个方法：

$.validator.addMethod('filesize', function(value, element, param) {
    // param = size (en bytes) 
    // element = element to validate (<input>)
    // value = value of the element (file name)
    return this.optional(element) || (element.files[0].size <= param) 
});

你会用它：

$('#formid').validate({
    rules: { inputimage: { required: true, accept: "png|jpe?g|gif", filesize: 1048576  }
    messages: { inputimage: "File must be JPG, GIF or PNG, less than 1MB" }
});

Answer 2