Javascript實現的分頁函數

From: IECN.Net ; Author: 鐘鐘

/**
* 分頁類構造
* 參數 nTotalList: 總條數
* 參數 nPageSize: 每頁顯示條數
* 參數 nPageNum: 當前頁碼
* 參數 sPageUrl: 分頁連結的URL，頁碼以[pn]代替，輸出時將被替換為實際頁碼
* 參數 nPageListSize: 頁碼列表（下拉框）中顯示的最多頁碼條數。該參數可省略，預設100
*/
function Pagination(nTotalList, nPageSize, nPageNum, sPageUrl, nPageListSize) {
this.totalList = nTotalList;
this.pageSize = nPageSize;
this.pageNum = nPageNum;
if (nTotalList == 0)
this.totalPages = 1;
else
this.totalPages = Math.floor((this.totalList-1)/this.pageSize + 1);
this.pageUrl = sPageUrl;
if (arguments[4])
this.pageListSize = nPageListSize;
else
this.pageListSize = 100;
}

/**
* 產生分頁，將HTML直接輸出
* 無參數
* 無傳回值
*/
Pagination.prototype.generate = function() {
var output = "";
output += "<table width=\"98%\" cellspacing=\"1\" cellpadding=\"3\" align=\"center\"><tr><td align=\"right\">";
output += "共 " + this.totalList + " 條 每頁 " + this.pageSize + " 條 當前第 ";
output += "<select onchange=\"if(this.value)location.href='" + this.pageUrl + "'.replace(/\\[pn\\]/,";
output += "this.value);\" align=\"absMiddle\" style=\"font:normal 9px Verdana,Arial,宋體;\">";
var firstPage = this.pageNum - Math.floor(this.pageListSize/2);
if (firstPage < 1)
firstPage = 1;
var lastPage = firstPage + this.pageListSize - 1;
if (lastPage > this.totalPages) {
lastPage = this.totalPages;
firstPage = lastPage - this.pageListSize + 1;
if (firstPage < 1)
firstPage = 1;
}
if (firstPage > 1) {
output += "<option value=\"1\">1</option>";
if (firstPage > 2)
output += "<option value=\"\">…</option>";
}
for (var p = firstPage; p <= lastPage; p++) {
output += "<option value=\"" + p + "\"";
if (p == this.pageNum)
output += " selected=\"yes\"";
output += ">" + p + "</option>";
}
if (lastPage < this.totalPages) {
if (lastPage < this.totalPages - 1)
output += "<option value=\"\">…</option>";
output += "<option value=\"" + this.totalPages + "\">" + this.totalPages + "</option>";
}
if (this.pageNum > this.totalPages)
output += "<option value=\"\" selected=\"yes\">頁碼超出範圍</option>";
output += "</select>";
output += "/" + this.totalPages + " 頁 ";
if (this.pageNum == 1) {
output += "[首頁] ";
output += "[上頁] ";
}
else {
output += "<a href=\"" + this.pageUrl.replace(/\[pn\]/, "1") + "\">[首頁]</a> ";
output += "<a href=\"" + this.pageUrl.replace(/\[pn\]/, this.pageNum-1) + "\">[上頁]</a> ";
}
if (this.pageNum == this.totalPages) {
output += "[下頁] ";
output += "[尾頁]";
}
else {
output += "<a href=\"" + this.pageUrl.replace(/\[pn\]/, this.pageNum+1) + "\">[下頁]</a> ";
output += "<a href=\"" + this.pageUrl.replace(/\[pn\]/, this.totalPages) + "\">[尾頁]</a> ";
}
output += "</td></tr></table>";
document.writeln(output);
}