以下脚本不做IP格式的判断，只判断两个IP是否在同一网段。
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例子，Javascript判断两个IP是否在同一网段。
复制代码 代码示例:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE>IP段信息检测_www.jb200.com</TITLE>
<script language="JavaScript" type="text/javascript">
function checkSameNetMask(value1,value2,netmask)
{
var ip1 = new Array();
var ip2 = new Array();
var nm = new Array();
ip1 = value1.split(".");
ip2 = value2.split(".");
nm = netmask.split(".");
var ip1_2s = "";
var ip2_2s = "";
var inm2s = "";
var index = 0;
for ( index = 0 ; index<4 ; index++ )
{
var ip_1 = new Array();
var ip_2 = new Array();
var n_m = new Array();
ip_1 = parseInt(ip1[index]).toString(2);
ip_2 = parseInt(ip2[index]).toString(2);
n_m = parseInt(nm[index]).toString(2);
var tindex;
for( tindex = 0; tindex<(8 - ip_1.length) ; tindex++)
{
ip1_2s +="0";
}
ip1_2s += ip_1;
for( tindex = 0; tindex<(8 - ip_2.length) ; tindex++)
{
ip2_2s +="0";
}
ip2_2s += ip_2;
for( tindex = 0; tindex<(8 - n_m.length) ; tindex++)
{
inm2s +="0";
}
inm2s += n_m;
}
var len = inm2s.length;
var ip_12 = new Array();
var ip_22 = new Array();
var n_m_2 = new Array();
ip_12 = ip1_2s.split("");
ip_22 = ip2_2s.split("");
n_m_2 = inm2s.split("");
for ( index = 0 ; index < len ; index++ )
{
if(n_m_2[index] == "1")
{
if(ip_12[index] != ip_22[index])
{
alert("不在同一网段");
return false;;
}
}
}
alert("在同一网段");
return true;
}
</script>
</HEAD>
<BODY>
<input name="Ip1" id="Ip1" maxlength=15 ><br>
<input name="Ip2" id="Ip2" maxlength=15 ><br>
<input name="netmask" id="netmask" maxlength=15 >
<input type="button" value="计算" onClick="checkSameNetMask( document.getElementById('Ip1').value , document.getElementById('Ip2').value , document.getElementById('netmask').value ); ">
</BODY>
</HTML>
