小编MTA*_*MTA的帖子

我创建了一个包含几列的表，其中一个是VARCHAR(250).

我在表中有很多行，我想将列的 DataType 更改为VARCHAR(500).

如果我右键单击该表并选择“更改表”，则可以更改列 DataType。

像这样更改数据类型是否安全？

我还能如何更改列数据类型？

更改 DataType 时是否有可能丢失表中的数据？

我有Bing html,我想解析它的结果:

    string BingRegex = "<div class=\"sb_tlst\"><h3><a href=\"(.*?)\"";
    string[] results = Regex.Matches(responseStr, BingRegex).Cast<Match>().Select(m => m.Value).ToArray();

我将结果发送到数组,但它将模式添加到每个结果,如:

<div class=\"sb_tlst\"><h3><a href=\"www.cnn.com\"
<div class=\"sb_tlst\"><h3><a href=\"www.google.com\"
<div class=\"sb_tlst\"><h3><a href=\"www.gmail.com\"

知道我怎么能解决这个问题并获得网址？

我有这个json字符串:

{"conn": "wifi", "result": "ok", "build_id": 0, "content": {"ad_instream": {"clickthrough": "", "tracking": {"impression": ["http:\\\/\\\/pubads.g.doubleclick.net\\\/pagead\\\/adview?ai=BcTWwqp7vUe3HGtDa0AHQjoCYCO3Fn_0EAAAAEAEgADgAWKWn-_lbYPmCgICcEIIBF2NhLXB1Yi0yNjE0NjY2MjYxNTc5NzQxsgEYd3d3LmRjbGstZGVmYXVsdC1yZWYuY29tugEJZ2ZwX2ltYWdlyAEJ2gEgaHR0cDovL3d3dy5kY2xrLWRlZmF1bHQtcmVmLmNvbS_AAgLgAgDqAiQ0MDYxL21vYmkueXRwd2F0Y2gubXVzaWMvbWFpbl8zOTk2Njn4AvzRHpADhAeYA-ADqAMB0ASQTuAEAaAGINgGAg\\u0026sigh=Ys7UKZRdfi0\\u0026adurl=http:\\\/\\\/pagead2.googlesyndication.com\\\/pagead\\\/imgad\\\/879366\\\/dot.gif?1960307723"]}, "title": "", "duration": 0, "message": "", "companion_image": "", "encrypted_id": "", "source": "", "stream_url": ""}, "branding": null, "allow_ratings": true, "sentiment_xsrf_token": "7M7BB4lZtPAP55lTgHX-uubKznZ8MTM3NDc0NDYxOEAxMzc0NjU4MjE4", "channel_subscriber_count": 6221321, "ptracking": "\\\/\\\/www.youtube.com\\\/ptracking?oid=VyEtjbeN302yXkP3Qulrog\\u0026ptchn=officialpsy\\u0026ptk=ygent\\u0026video_id=9bZkp7q19f0\\u0026pltype=content", "next_url": "\\\/related?v=9bZkp7q19f0\\u0026page=2", "subscribe_xsrf_token": "opnXNXthIo8ifJHxFIzcoDeCFxd8MTM3NDc0NDYxOEAxMzc0NjU4MjE4", "player_data": {}, "video": {"player_type": "html5fs", "profile_url": "\\\/user\\\/officialpsy", "title": "PSY - GANGNAM STYLE (\\uac15\\ub0a8\\uc2a4\\ud0c0\\uc77c) M\\\/V", "duration": "4:13", "watch_link": "\\\/watch?v=9bZkp7q19f0", "public_name": "officialpsy", "thumbnail_for_watch": "http:\\\/\\\/i.ytimg.com\\\/vi\\\/9bZkp7q19f0\\\/hqdefault.jpg?w=320\\u0026h=192\\u0026sigh=Y3_yUSuTAw53AwGBBy62wc6U5W0", "description": "PSY - Gangnam Style (\\uac15\\ub0a8\\uc2a4\\ud0c0\\uc77c) \\n\\u25b6 NOW available on iTunes: http:\\\/\\\/Smarturl.it\\\/psygangnam\\n\\u25b6 Official PSY …

我在我的HTML中有这个,我想删除与ad spf-nolink类的div

<div class="ad spf-nolink">
<ol id="search-results" class="result-list context-data-container">
<div class="ad spf-nolink">

我试着这样做:

var adElem = $('#ad spf-nolink');
if (adElem == null) {
    alert('1');
} else {
    $("#ad spf-nolink").removeClass();

    alert('3');
}

并且2 divs仍然在那里,任何想法可能是什么问题？