option

What values can appear in the “selected” attribute of the “option” tag?

吃可爱长大的小学妹 提交于 2019-11-26 04:48:20
问题 I have some markup similar to the following: <select> <option selected=\"selected\">Apple</option> <option selected=\"\">Orange</option> </select> In this case, \"Orange\" shows as the selected item. I would have expected making the selected attribute blank would undo its effects. Is there a way to write this without simply leaving the attribute out? 回答1: Different browser may treat this attribute differently. According to the MSDN documentation (for Internet Explorer): To select an item in

What parameter parser libraries are there for C++? [closed]

一个人想着一个人 提交于 2019-11-26 03:24:28
I'd like to pass parameters to my C++ program in the following manner: ./myprog --setting=value Are there any libraries which will help me to do this easily? See also Argument-parsing helpers for C and Unix Boost.Program_options Marcin Gil GNU GetOpt . A simple example using GetOpt: // C/C++ Libraries: #include <string> #include <iostream> #include <unistd.h> // Namespaces: using namespace std; int main(int argc, char** argv) { int opt; bool flagA = false; bool flagB = false; // Shut GetOpt error messages down (return '?'): opterr = 0; // Retrieve the options: while ( (opt = getopt(argc, argv,

How do you remove all the options of a select box and then add one option and select it with jQuery?

隐身守侯 提交于 2019-11-26 03:24:27
问题 Using core jQuery, how do you remove all the options of a select box, then add one option and select it? My select box is the following. <Select id=\"mySelect\" size=\"9\"> </Select> EDIT: The following code was helpful with chaining. However, (in Internet Explorer) .val(\'whatever\') did not select the option that was added. (I did use the same \'value\' in both .append and .val .) $(\'#mySelect\').find(\'option\').remove().end() .append(\'<option value=\"whatever\">text</option>\').val(\

How do you remove all the options of a select box and then add one option and select it with jQuery?

霸气de小男生 提交于 2019-11-26 02:27:27
Using core jQuery, how do you remove all the options of a select box, then add one option and select it? My select box is the following. <Select id="mySelect" size="9" </Select> EDIT: The following code was helpful with chaining. However, (in Internet Explorer) .val('whatever') did not select the option that was added. (I did use the same 'value' in both .append and .val .) $('#mySelect').find('option').remove().end().append('<option value="whatever">text</option>').val('whatever'); EDIT: Trying to get it to mimic this code, I use the following code whenever the page/form is reset. This select

It is bad to put <span /> tags inside <option /> tags, only for string manipulation not styling?

假装没事ソ 提交于 2019-11-26 02:24:29
问题 I would like to make groups of the text content of an <option /> tag. Say I have the following: <option>8:00 (1 hour)</option> , the time pattern 8:00 can be modified, then the text in parenthesis (1 hour) can also be modified. I was thinking of doing something like <option> <span>8:00</span> <span> (1 hour)</span> </option> It is bad to put <span /> tags inside <option /> tags, only for string manipulation not styling? 回答1: From the HTML 4.01 spec: <!ELEMENT OPTION - O (#PCDATA) --

Is there a way to apply a CSS style on HTML5 datalist options?

心已入冬 提交于 2019-11-26 02:24:11
问题 I would like to modify the way that the list of the different options of my datalist are displayed. Is it possible to apply on it some CSS properties ? <input list=\"languages\" id=\"language_id\"> <datalist id=\"languages\"> <option value=\"html\">HTML</option> <option value=\"java\">Java</option> <option value=\"perl\">Perl</option> <option value=\"php\">PHP</option> <option value=\"ruby-on-rails\">Ruby on Rails</option> </datalist> I tried option { background: red; } but it does not seem

What parameter parser libraries are there for C++? [closed]

为君一笑 提交于 2019-11-26 01:06:31
问题 I\'d like to pass parameters to my C++ program in the following manner: ./myprog --setting=value Are there any libraries which will help me to do this easily? See also Argument-parsing helpers for C and Unix 回答1: Boost.Program_options 回答2: GNU GetOpt. A simple example using GetOpt: // C/C++ Libraries: #include <string> #include <iostream> #include <unistd.h> // Namespaces: using namespace std; int main(int argc, char** argv) { int opt; bool flagA = false; bool flagB = false; // Shut GetOpt

using href links inside <option> tag

与世无争的帅哥 提交于 2019-11-25 23:36:38
问题 I have the following HTML code: <select name=\"forma\"> <option value=\"Home\">Home</option> <option value=\"Contact\">Contact</option> <option value=\"Sitemap\">Sitemap</option> </select> How can I make Home , Contact and Sitemap values as links? I used the following code and as I expected it didn\'t work: <select name=\"forma\"> <option value=\"Home\"><a href=\"home.php\">Home</a></option> <option value=\"Contact\"><a href=\"contact.php\">Contact</a></option> <option value=\"Sitemap\"><a

python模块之configparser

耗尽温柔 提交于 2019-11-25 20:54:26
configparser configParser 模块用于操作配置文件 注:Parser汉译为“解析”之意。 配置文件的格式与windows ini文件类似,可以包含一个或多个节(section),每个节可以有多个参数(键=值或者键:值)。 为了更好的理解本文,我们先了解一下配置文件的组成及命名:配置文件(INI文件)由节(section)、键、值组成。 样例配置文件config.ini [book] title = ConfigParser模块教程 time = 2018-01-12 11:47:37 [size] size = 1024 [other] blog = https://blog.51cto.com/kexiaoke 在config.ini里面出现了三个节(section),分别是book,size,other book里面有两个键值对,size和other里面各一个。 读取配置文件 read(filename) 直接读取ini文件内容 sections() 得到所有的section,并以列表的形式返回 options(section) 得到该section的所有option items(section) 得到该section的所有键值对 get(section,option) 得到section中option的值,返回为string类型 getint

深圳Web前端学习:跨域

喜夏-厌秋 提交于 2019-11-25 20:16:14
深圳Web前端学习:跨域 在web有一种现象:不同的域名之间相互分享资源(信息)并进行通信。 这种现象叫做:跨域。 表面上看起来多个站点之间的来往增加是非常好的,但是其中弊端却是更大的。因为你不知道其他站点会拿你分享给他的信息做什么事情。所以出于安全性的考虑,在web中跨域这种现象默认是不允许的。 如果在两个或多个站点提前说好,我可以把我们站点客户端的数据分享给你,这样就会被浏览器默认阻止,因为他们是不同域的数据,所以我们就需要通过技术手段来实现了。 能够实现跨域的手段很多,总结下来要有8个之多(可能有更多只是我不知道而已),但是今天我们只介绍其中最为常见的一种:jsonP。 本章知识点: 同源策略 天生就能跨域的标签 jsonP的基本实现 jsonP请求百度的数据 jsonP的优缺点 同源策略 同源策略是浏览器出于安全性考虑指定的一套策略,目的是阻止不同域之间的信息通信。 那么什么是同源策略? 即协议(http),域名(www.xxx.com),端口(80)一致。 // 目标域名 www.xxx.com htttp://www.xxx.com (同源) htttp://www.xxx.com/index.html (同源) htttps://www.xxx.com/index.html (不同源,协议不同) htttp://xxx.com/index.html (不同源