//判断浏览器是否支持placeholder属性
function isSupportPlaceholder() {
var input = document.createElement('input');
return 'placeholder' in input;
}
如果支持,返回true,否认在false;
运用:
// 如果不支持placeholder,用jQuery来完成
if(!isSupportPlaceholder()) {
// 遍历所有input对象, 除了密码框
$('input').not("input[type='password']").each(function() {
var self = $(this);
var val = self.attr("placeholder");
input(self, val);
}
);
/**
* 对password框的特殊处理
* 1.创建一个text框
* 2.获取焦点和失去焦点的时候切换
*/
$('input[type="password"]').each(
function() {
var pwdField = $(this);
var pwdVal = pwdField.attr('placeholder');
var pwdId = pwdField.attr('id');
// 重命名该input的id为原id后跟1
pwdField.after('<input id="' + pwdId +'1" type="text" value='+pwdVal+' autocomplete="off" />');
var pwdPlaceholder = $('#' + pwdId + '1');
pwdPlaceholder.show();
pwdField.hide();
pwdPlaceholder.focus(function(){
pwdPlaceholder.hide();
pwdField.show();
pwdField.focus();
});
pwdField.blur(function(){
if(!pwdField.val()) {
pwdPlaceholder.show();
pwdField.hide();
}
});
}
);
}