function resizeTableCol(id){
    var i,
        self,
        table = document.querySelector(id),
        header = table.rows[0],
        tableX = header.clientWidth,
        length = header.cells.length;
    for (i = 0; i < length; i++) {
        header.cells[i].onmousedown = function () {
            self = this;
            if (event.offsetX > self.offsetWidth - 10) {
                self.mouseDown = true;
                self.oldX = event.x;
                self.oldWidth = self.offsetWidth;
            }
        };
        header.cells[i].onmousemove = function () {
            if (event.offsetX > this.offsetWidth - 10) {
                this.style.cursor = 'col-resize';
            } else {
                this.style.cursor = 'default';
            }
            if (self == undefined) {
                self = this;
            }
            if (self.mouseDown != null && self.mouseDown == true) {
                self.style.cursor = 'default';
                if (self.oldWidth + (event.x - self.oldX) > 0) {
                    self.width = self.oldWidth + (event.x - self.oldX);
                }
                self.style.width = self.width;
                table.style.width = tableX + (event.x - self.oldX) + 'px';
                self.style.cursor = 'col-resize';
            }
        };
        table.onmouseup = function () {
            if (self == undefined) {
                self = this;
            }
            self.mouseDown = false;
            self.style.cursor = 'default';
            tableX = header.clientWidth;
        };
    }
}

//使用时传入table的id名
setTimout(resizeTableCol('#table'),300);