/** *jQuery rposition *fix:要定位的元素 *rel：相对定位的元素 *options:{},align:左右对齐;vlign:垂直对齐;xleft:水平补给值;xleft:垂直补给值;adjust:是否相对窗口自动调整;rwindow:定位相对于窗口(align&vlign为center时垂直或水平居中); */ (function(win,$){ win.rposition=function(fix,rel,options){ var rectLeft,rectTop,rectH=fix.outerHeight(),rectW=fix.outerWidth(),wh=$(window).height(),ww=$(window).width(), sT=$(document).scrollTop(),sL=$(document).scrollLeft(), defaults={ align:"left", vlign:"top", xleft:0, xtop:0, adjust:true, rwindow:false }, options = $.extend(defaults, options); var rectRel={ l:$(rel).offset().left, t:$(rel).offset().top, w:$(rel).outerWidth(), h:$(rel).outerHeight() }; switch(options.align){ case "left": rectLeft=rectRel.l;break; case "right": rectLeft=rectRel.l+rectRel.w;break; case "center": rectLeft=rectRel.l+rectRel.w/2;break; case "rleft": rectLeft=rectRel.l-rectW;break; default: rectLeft=rectRel.l; }; switch(options.vlign){ case "top": rectTop=rectRel.t;break; case "center": rectTop=rectRel.t+rectRel.h/2;break; case "vbottom": rectTop=rectRel.t-rectH; break; case "bottom": default: rectTop=rectRel.t+rectRel.h; }; if(options.rwindow){ if(options.align=="center")rectLeft=(ww-rectW)/2+sL; if(options.vlign=="center")rectTop=(wh-rectH)/2+sT; }; if(options.adjust){ if(rectLeft+rectW>ww+sL){rectLeft-=(rectLeft+rectW)-(ww+sL)} if(rectTop+rectH>wh+sT){rectTop=rectRel.t-rectH;} }; $(fix).css({"left":rectLeft+options.xleft,"top":rectTop+options.xtop}); } })(window,jQuery)