/****
get pager ranger, 

showPageNumber -- how many pages show in pager
pageId --current pageId
******/
function GetPagerRange(totalItemNumber, pageId, pageSize, showPageNumber) {
    if(totalItemNumber < pageSize)
        return '';
    pageId = parseInt(pageId);
    var totalPageNumber = Math.ceil(totalItemNumber / pageSize);
    var showPageNumber1stHalf = Math.ceil(showPageNumber / 2);
    var showPageNumber2ndHalf = Math.floor(showPageNumber / 2);
    var startIndex = 1;
    var endIndex = totalPageNumber;
    if (totalPageNumber < showPageNumber) {
        startIndex = 1;
        endIndex = totalPageNumber;
    } else if (pageId <= showPageNumber2ndHalf) {
        startIndex = 1;
        endIndex = showPageNumber;
    } else if (pageId > totalPageNumber - showPageNumber2ndHalf) {
        startIndex = totalPageNumber - showPageNumber + 1;
        endIndex = totalPageNumber;

    } else {
        startIndex = pageId - showPageNumber1stHalf + 1;
        endIndex = pageId + showPageNumber2ndHalf;
    }
    var pager = $('<div class="pager" style="cursor:default;">');
    var html = '<div class="pager" style="cursor:default;">';
    for (i = startIndex; i <= endIndex; i++) {
        var pageStr = i.toString();
        if (i < 10) {
            pageStr = '&nbsp;' + pageStr;
        }
        if (pageId == i) {
            html += '&nbsp;<b>' + pageStr + '</b>';
        }
        else {
            html += '&nbsp;<a class="pagerLink" style="cursor:pointer;">' + pageStr + '</a>';
        }
    }

    html += "</div>";
   //return pager;
    return html;
}