C# 不要用逗号分割字符串

Question

I am using Xamarin.Forms to create a data collection application. One particular feature of this app is to export the data via csv. When captured the data is written to a text file using the following method:

 public void WriteToFile(string CompanyName, string Website, string FirsttName, string LastName, string JobTitle, string Phone, string Email, string Solution, string Notes, string ContactOwner, string EventName)
    {
        string path = Environment.GetFolderPath(Environment.SpecialFolder.Personal);
        string filename = System.IO.Path.Combine(path, "Prospects.txt");
        string lineToBeAdded = string.Format("{0},{1},{2},{3},{4},{5},{6},{7},{8},{9},{10}", CompanyName, Website, FirsttName, LastName, JobTitle, Phone, Email, Solution, Notes, ContactOwner, EventName);
        File.AppendAllText(filename, lineToBeAdded + Environment.NewLine);


    }

My problem is that in the variable NOTES the user uses commas in their description which messes up the structure of the csv.

How do I force ignore commas in this string?

Answer 1

To escape comma warp each column in double quotes, to scape double qoutes use 2 double qoutes instead of each:

 string lineToBeAdded = string.Format("\"{0}\",\"{1}\",\"{2}\",\"{3}\",\"{4}\",\"{5}\",\"{6}\",\"{7}\",\"{8}\",\"{9}\",\"{10}\"", 
CompanyName.Replace("\"","\"\""),
 Website.Replace("\"","\"\""),
 FirsttName.Replace("\"","\"\""),
 LastName.Replace("\"","\"\""),
 JobTitle.Replace("\"","\"\""),
 Phone.Replace("\"","\"\""),
 Email.Replace("\"","\"\""),
 Solution.Replace("\"","\"\""),
 Notes.Replace("\"","\"\""),
 ContactOwner.Replace("\"","\"\""),
 EventName.Replace("\"","\"\""));

Answer 2

Solution

Create this function:

string GetCsvLine(params string[] fields) =>
   string.Join(",", fields.Select(x => $"\"{x.Replace("\"", "\"\"")}\""));

And call it like this, replacing the line in your example code that initializes "lineToBeAdded":

string lineToBeAdded = GetCsvLine(CompanyName, Website, FirsttName, LastName, JobTitle, Phone, Email, Solution, Notes, ContactOwner, EventName);

Explanation

Refer here - RFC4180 - to the specification for CSV:

Summarizing:

• A field must be enclosed in double-quotes, if it contains a comma, a line break, or a double-quote.
• Any double-quotes within a field must themselves be doubled.
• Bonus: using 'params' and LINQ allows you to call this method with a variable number of arguments, eliminating the need for a format string with the exact number of placeholders.

Answer 3

Also you don't have to use comma's, you can use a | or something else the user doesn't use.

To make it even more friendly you can specify the delimiter in the first line, excel supports that I know.

sep=|
header1|header2|header3
1,2|2,3|3,4