使表格的标题列可左右拉伸jquery插件封装_jquery

/*
Writen by mlcactus, 2014-11-24
这是我封装的一个jquery插件，能够使table的各列可以左右拉伸，从而使宽度变小或变大
用法：
单个table：$("#table_id").tableresize();
页面所有table：$("table").tableresize();
*/
(function ($) {
$.fn.tableresize = function () {
var _document = $("body");
$(this).each(function () {
if (!$.tableresize) {
$.tableresize = {};
}
var _table = $(this);
//设定ID
var id = _table.attr("id") || "tableresize_" + (Math.random() * 100000).toFixed(0).toString();
var tr = _table.find("tr").first(), ths = tr.children(), _firstth = ths.first();
//设定临时变量存放对象
var cobjs = $.tableresize[id] = {};
cobjs._currentObj = null, cobjs._currentLeft = null;
ths.mousemove(function (e) {
var _this = $(this);
var left = _this.offset().left, top = _this.offset().top, width = _this.width(), height = _this.height(), right = left + width, bottom = top + height, clientX = e.clientX, clientY = e.clientY;
var leftside = !_firstth.is(_this) && Math.abs(left - clientX) <= 5, rightside = Math.abs(right - clientX) <= 5;
if (cobjs._currentLeft || clientY > top && clientY < bottom && (leftside || rightside)) {
_document.css("cursor", "e-resize");
if (!cobjs._currentLeft) {
if (leftside) {
cobjs._currentObj = _this.prev();
}
else {
cobjs._currentObj = _this;
}
}
}
else {
cobjs._currentObj = null;
}
});
ths.mouseout(function (e) {
if (!cobjs._currentLeft) {
cobjs._currentObj = null;
_document.css("cursor", "auto");
}
});
_document.mousedown(function (e) {
if (cobjs._currentObj) {
cobjs._currentLeft = e.clientX;
}
else {
cobjs._currentLeft = null;
}
});
_document.mouseup(function (e) {
if (cobjs._currentLeft) {
cobjs._currentObj.width(cobjs._currentObj.width() + (e.clientX - cobjs._currentLeft));
}
cobjs._currentObj = null;
cobjs._currentLeft = null;
_document.css("cursor", "auto");
});
});
};
})(jQuery);