正则提取要选择题的选项

如下题匹配选项：

(1) 设集合 $A=[-1,2], B=\left{y \mid y=x^{2}, x \in A\right}$, 则 $A\cap B=$
A. $[1,4]$
B. $[1,2]$
C. $[-1,0]$
D. $[0,2]$

直接上代码：

    function getOption(str,from,to)
    {
        var r = 'var reg = /[\(]*'+from+'[:|：|、|.]{1}(.*?)[\s]?'+ to +'/';
        // console.log(r);
        eval(r);
        var arr = str.match(reg);
        console.log(arr);
        return arr[1].replace('<br/>','').replace('</p><p style=\"white-space: normal;\">','');
        //return str.match(reg)[1];
    }

格式化数据：

    function formatContent(content)
    {
        content = content.replace('\(A\)','A.').replace('\(B\)','B.').replace('\(C\)','C.').replace('\(D\)','D.').replace('\(E\)','E.').replace('\(F\)','F.'); 
        content = content.replace('<br/>','');
        content = content.replace('<br>','');
        content = content.replace('</p><p>'); 
        content = content.replace('<x','\\lt x');

        return content;    
    }

设置选项：

    function setChoiceItem()
    {
        var list =['A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q'];
        var ue = UE.geEditor('question-content');
        var content = formatContent(ue.getContent());
        console.log(content);
        var str = content;

        //console.log(getOption(str,'A','B'));
        //console.log(getOption(str,'B','C'));
        //console.log(getOption(str,'C','D'));
        //console.log(getOption(str,'D','$'));

        //$('p.optionContent:eq(0)').html(getOption(content,'A','B'));
        //$('p.optionContent:eq(1)').html(getOption(content,'B','C'));
        //$('p.optionContent:eq(2)').html(getOption(content,'C','D'));
        //$('p.optionContent:eq(3)').html(getOption(content,'D','$'));
        
        var len = $('p.optionContent').length; 

        $('p.optionContent').each(function(index,e){

            console.log(list[index]);console.log(len);

            var start = list[index];
            var end = list[index+1];
            if(index == len-1) 
            {
                end='$';
            }

            $(this).html(getOption(content,start,end));

        });

    }