C＃字符串解析

Question

我有这样的字符串

string temp = "'ADDR_LINE_2','MODEL','TABLE',5,'S','Y','C40','MUL,NBLD,NITA,NUND','','Address line 2'"

每对单引号都是一个以逗号分隔的字段。 我想清空字符串中的第8个字段。 我不能简单地执行replace("MUL,NBLD,NITA,NUND","")因为该字段可以包含任何内容。 还请注意，第4个字段是数字，因此在5周围没有单引号。

我该如何实现？

Answer 1

static void Main()
{
    var temp = "'ADDR_LINE_2','MODEL','TABLE',5,'S','Y','C40','MUL,NBLD,NITA,NUND','','Address line 2'";

    var parts = Split(temp).ToArray();
    parts[7] = null;
    var ret = string.Join(",", parts);

    // or replace the above 3 lines with this...        
    //var ret = string.Join(",", Split(temp).Select((v,i)=>i!=7 ? v : null));

    //ret == "'ADDR_LINE_2','MODEL','TABLE',5,'S','Y','C40',,'','Address line 2'"
}

public static IEnumerable<string> Split(string input, char delimiter = ',', char quote = '\'')
{
    string temp = "";
    bool skipDelimiter = false;

    foreach (var c in input)
    {
        if (c == quote)
            skipDelimiter = !skipDelimiter;
        else if (c == delimiter && !skipDelimiter)
        {
            //do split
            yield return temp;
            temp = "";
            continue;
        }

        temp += c;
    }
    yield return temp;
}

Answer 2

我在下面做了一个小实现。 我在评论中解释了逻辑。 基本上，您想编写一个简单的解析器来完成您描述的内容。

edit0：刚意识到我做的与您要求的相反。.现在修复

edit1：将字符串替换为null，而不是从逗号分隔的列表中删除整个字段。

    static void Main(string[] args)
    {
        string temp = "'ADDR_LINE_2','MODEL','TABLE',5,'S','Y','C40','MUL,NBLD,NITA,NUND','','Address line 2'";
        //keep track of the single quotes
        int singleQuoteCount= 0;
        //keep track of commas
        int comma_count = 0;
        String field = "";
        foreach (Char chr in temp)
        {
            //add to the field string if we are not between the 7th and 8th comma not counting commas between single quotes
            if (comma_count != 7)
                field += chr;
            //plug in null string between two single quotes instead of whatever chars are in the eigth field.
            else if (chr == '\'' && singleQuoteCount %2 ==1)
                field += "\'',";

            if (chr == '\'') singleQuoteCount++;
            //only want to add to comma_count if we are outside of single quotes.
            if (singleQuoteCount % 2 == 0 && chr == ',') comma_count++;

        }
    }

Answer 3

如果在字段内（例如：“ MUL-NBLD-NITA-NUND”）使用“-”（或其他字符）代替“，”，则可以使用以下代码：

    static void Main(string[] args)
    {
        string temp = "'ADDR_LINE_2','MODEL','TABLE',5,'S','Y','C40','MUL-NBLD-NITA-NUND','','Address line 2'";
        temp = replaceField(temp, 8);
    }

    static string replaceField(string list, int field)
    {
        string[] fields = list.Split(',');
        string chosenField = fields[field - 1 /*<--Arrays start at 0!*/];

        if(!(field == fields.Length))
            list = list.Replace(chosenField + ",", "");
        else
            list = list.Replace("," + chosenField, "");

        return list;
    }

    //Return-Value: "'ADDR_LINE_2','MODEL','TABLE',5,'S','Y','C40','','Address line 2'"