[RESOLVED] string builder question

[Crash893]

I have a few lines i borrowed from the codebank here for my orginal vb project

i am having trouble converting it over to c#

in partular the line line.Append(","c)

im just not sure what the c is doing ive been reading through the stringbuilder on msdn but im still not sure what the eqivlancy in c# should be


can anyone help point me in the right direction
thanks

Dim line As New System.Text.StringBuilder
            Dim index As Integer
 
            If header = True Then
 
                'Iterate over all the columns in the table and get the column names.
                For index = 0 To table.Columns.Count - 1 Step 1
 
                    If index > 0 Then
                        'Put a comma between column names.
                        line.Append(","c)
                    End If
 
                    'Precede and follow each column name with a double quote
                    'and escape each double quote with another double quote.
                    line.Append(""""c)
                    line.Append(table.Columns(index).ColumnName.Replace("""", """"""))
                    line.Append(""""c)

[wild_bill]

Don't use the c to specify character

sb.Append(",");

[Crash893]

well crap that was easy

what does the c do anyway

[wild_bill]

The c tells visual basic that it is a character type, not string type.

[Crash893]

if i use the line


line.Append(""""c)

i get ") expected"

but if i put in a ) i get a invaild expression term

any ideas?

[mendhak]

line.Append("\""c);

[Crash893]

not that im not greatfull for the answer

could you explain it to me a little so i understand what the \ is for?

so i can apply it to this line
line.Append(table.Columns(index).ColumnName.Replace("\"", """"""))

------------------------------------------------------------^
Here

also shouldnt it be

line.Append("\"");

[Harsh Gupta]

\ in C#, C++, and C (or maybe some other languages), when followed by some specific character to result in some meaningful string, is known as Escape Sequence.

What character escape sequences are available in C#

[jmcilhinney]

In VB this is appending a Char object to a StringBuilder:

line.Append(","c)

while this is appending a String object to a StringBuilder:

line.Append(",")

In C# this is appending a Char object to a StringBuilder:

line.Append(',');

while this is appending a String object to a StringBuilder:

line.Append(",");

VB does NOT support C-style escape sequences in strings, which is why you have to use concatenation to insert a line break in a string in VB. The ONLY character that requires escaping in VB is the double quote, to indicate that it is a literal character and not the end of the string. In VB a literal double quote gets escaped with another double quote, i.e. for every one double quote you want to appera in your string you have to input two double quotes.

C# DOES support C-style escape sequences, being based on C syntax. That means that any special characters in a C# string must be escaped with a backslash to indicate that they are special. These include a tab (\t), a carriage return (\r) and a line feed (\n). Because the backslash itself is a special character it must also be escaped with a backslash when you want it to appear as a literal character, i.e. for every one backslash you want to appear in your string you have to input two backslashes. C# has the same issue that VB does with the double quote in that it would normally indicate the end of the string, so if you want a literal double quote to appear in your string you must escape it, but in C# strings all escaping is done with the backslash.

Note that C# also supports the verbatim string operator, which tells the compiler to treat every character in the string as a literal. This is most useful for paths. Normally you'd have to write a path like this:

string myPath = "C:\\Folder\\Subfolder\\MyFile.txt";

with all the delimiters escaped, but C# allows you to do this:

string myPath = @"C:\Folder\Subfolder\MyFile.txt";

Because the verbatim string operator says that all characters are literal you cannot include ANY characters that require escaping, which includes double quotes.

[Crash893]

so a \" = ""



here is what i came up with

line.Append(table.Columns(index).ColumnName.Replace("\"", "\"\""));