体会：异步请求数据库（实例）
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Code1
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">2
<html xmlns="http://www.w3.org/1999/xhtml" >3
<head><title>4
xxx药品管理系统5
</title><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><link href="Style.css" rel="stylesheet" type="text/css" />6
<style type="text/css">
7
<!--8
body {}{9
background-image: url(images/login_bg.jpg);10
background-repeat: repeat-x;11
}12
-->13
</style>14
<script language="javascript">15
//创建xmlhttp对象16
function createxmlhttp()17
{18
var xmlhttp=false;19
try 20
{21
xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");22
} 23
catch (e) 24
{25
try 26
{27
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");28
} 29
catch (e) 30
{31
xmlhttp = false;32
}33
}34
if (!xmlhttp && typeof XMLHttpRequest!='undefined') 35
{36
xmlhttp = new XMLHttpRequest();37
if (xmlhttp.overrideMimeType)38
{39
//设置MiME类别 40
xmlhttp.overrideMimeType('text/xml');41
}42
}43
return xmlhttp; 44
}45
//向服务器获取数据46
function getdata(url)47
{48
var xmlhttp=createxmlhttp();49
if(!xmlhttp)50
{51
alert("你的浏览器不支持XMLHTTP！！");52
return;53
}54
xmlhttp.onreadystatechange=requestdata;55
xmlhttp.open("GET",url,true);56
xmlhttp.setRequestHeader("If-Modified-Since","0");57
xmlhttp.send(null);58
function requestdata()59
{60
if(xmlhttp.readyState==4)61
{62
if(xmlhttp.status==200)63
{64
65
}66
}67
68
}69
}70
//向服务器发送数据71
function postdata(url)72
{73
var xmlhttp=createxmlhttp();74
if(!xmlhttp)75
{76
alert("你的浏览器不支持XMLHTTP！！");77
return;78
}79
xmlhttp.onreadystatechange=requestdata;80
xmlhttp.open("POST", url, true);81
xmlhttp.setRequestHeader("If-Modified-Since","0");82
xmlhttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded");83
xmlhttp.send(null);84
function requestdata()85
{86
if(xmlhttp.readyState==4)87
{88
if(xmlhttp.status==200)89
{90
document.getElementById("strUser").value=xmlhttp.responseText;91
}92
}93
}94
}95
</script>96
<SCRIPT LANGUAGE="JavaScript"> 97
function enterkey() 98
{99
if(event.keyCode==13 && event.srcElement.type !="BUTTON" && event.srcElement.type!="SUBMIT") 100
event.keyCode=9; 101
} 102
</SCRIPT> 103
</head>104
<body>105
<form name="form1" method="post" action="default.aspx" onkeypress="javascript:return WebForm_FireDefaultButton(event, 'ImageButton1')" id="form1">106
<div>107
<input type="hidden" name="__EVENTTARGET" id="__EVENTTARGET" value="" />108
<input type="hidden" name="__EVENTARGUMENT" id="__EVENTARGUMENT" value="" />109
<input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE" value="/wEPDwUKLTkzMzY3NDAzOQ9kFgICAw9kFgYCAQ8PZBYGHgZvbkJsdXIFKXBvc3RkYXRhKCdhamF4LmFzcHg/c3RydXNlcj0nK3RoaXMudmFsdWUpHgdvbkZvY3VzBQ10aGlzLnZhbHVlPScnHglvbmtleWRvd24FC2VudGVya2V5KCk7ZAIDDw9kFgIfAgULZW50ZXJrZXkoKTtkAgUPD2QWAh8CBTxpZihldmVudC5rZXlDb2RlPT0xMyl7ZG9jdW1lbnQuYWxsKCdJbWFnZUJ1dHRvbjEnKS5jbGljaygpO31kGAEFHl9fQ29udHJvbHNSZXF1aXJlUG9zdEJhY2tLZXlfXxYCBQxJbWFnZUJ1dHRvbjEFDEltYWdlQnV0dG9uMleZks/M5q6rlQx1Z14xDSsgVeRA" />110
</div>111
112
<script type="text/javascript">113
<!--114
var theForm = document.forms['form1'];115
if (!theForm) {116
theForm = document.form1;117
}118
function __doPostBack(eventTarget, eventArgument) {119
if (!theForm.onsubmit || (theForm.onsubmit() != false)) {120
theForm.__EVENTTARGET.value = eventTarget;121
theForm.__EVENTARGUMENT.value = eventArgument;122
theForm.submit();123
}124
}125
// -->126
</script>127
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<script src="/WebResource.axd?d=nDDjtNjQLC3Gn9Lk57tbOg2&t=633529327109947414" type="text/javascript"></script>130
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<script src="/WebResource.axd?d=gJ1ctCJEwqzlj2juTZpXfA2&t=633529327109947414" type="text/javascript"></script>133
<div>134
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<table width="1002" border="0" align="center" cellpadding="0" cellspacing="0">136
<tr>137
<td width="1002"><img src="images/login_top.jpg" width="1002" height="260" /></td>138
</tr>139
<tr>140
<td height="201" valign="middle" background="images/login_bg1.jpg">141
<table width="208" border="0" align="center" cellpadding="0" cellspacing="0">142
<tr>143
<td width="62" class="Whilt">用户名：</td>144
<td colspan="2">145
<input name="strUser" type="text" id="strUser" tabindex="1" class="login_input" onBlur="postdata('ajax.aspx?struser='+this.value)" onFocus="this.value=''" onkeydown="enterkey();" /> </td>146
</tr>147
<tr class="Whilt">148
<td height="5" colspan="3"></td>149
</tr>150
<tr>151
<td class="Whilt">密 码：</td>152
<td colspan="2">153
<input name="pwd" type="password" id="pwd" tabindex="1" class="login_input" onkeydown="enterkey();" /> </td>154
</tr>155
<tr class="Whilt">156
<td height="5" colspan="3"></td>157
</tr>158
<tr>159
<td class="Whilt">验证码：</td>160
<td width="67">161
<input name="code" type="text" id="code" tabindex="2" class="login_Code" onkeydown="if(event.keyCode==13){document.all('ImageButton1').click();}" />162
</td>163
<td width="79"> <img src="ValidCode.aspx" id="imgVerify" alt="看不清？点击更换" name="imgVerify" height="25" style="cursor:hand" onclick="this.src=this.src+'?'" /></td>164
</tr>165
<tr class="Whilt">166
<td height="5" colspan="3"></td>167
</tr>168
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<tr>170
<td height="45" colspan="3" align="center" valign="bottom">171
<input type="image" name="ImageButton1" id="ImageButton1" tabindex="3" src="images/login_submit.jpg" style="border-width:0px;" />172
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<input type="image" name="ImageButton2" id="ImageButton2" tabindex="4" src="images/login_reset.jpg" style="border-width:0px;" /></td>174
</tr>175
</table>176
</td>177
</tr>178
<tr>179
<td height="239" valign="top" background="images/login_bg2.jpg"><table width="928" border="0" align="right" cellpadding="0" cellspacing="0">180
<tr>181
<td><img src="images/login_pic.jpg" width="56" height="26" /></td>182
<td> </td>183
</tr>184
<tr>185
<td colspan="2" align="right" class="Whilt text" style="padding-right:10px">浙江省医院xxxxxx网 版权所有 © 2008 All Right Reserved. 浙江省xxxxxx主办<br />186
地址：杭州市 (310003) <br />187
建议浏览器IE6.0+ 分辨率:1024*768以上 浙ICP备xxxxxx号</td>188
</tr>189
</table></td>190
</tr>191
</table>192
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</div>194
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<div>196
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<input type="hidden" name="__EVENTVALIDATION" id="__EVENTVALIDATION" value="/wEWBgKfiZq5BgKW+vj0DALGmdGVDAKzmc2yBwLSwpnTCALSwtXkAgb2NeCoYoLuSNJRB62zi2CMpQx1" />198
</div>199
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<script type="text/javascript">201
<!--202
WebForm_AutoFocus('strUser');// -->203
</script>204
</form>205
</body>206
</html>207
