You may need to GetField for a single field
Other things with the row you might need to do. GetRecord also does not advance the reader to allow you to do Separating Read and ReadHeader allows you to do other things with the header row before
ReadHeader will read the row into CsvHelper as the header values. using (var reader = new StreamReader("path\\to\file.csv")) using (var reader = new StreamReader("path\\to\\file.csv"))Ĭreating a class map is the recommended way of mapping files in CsvHelper because it's a To use the mapping, we need to register it in the context. In this case, we can use a fluent ClassMap to do the mapping. What if we don't have control over the class we want to map to so we can't add attributes to it? There are many other attributes you can use also. Use attributes instead of changing the header matching. Let's use our lower case header example from before and see how we can The IndexAttribute allows you to specify which position the CSV field is that you want to use One way to do this is with attribute mapping. We can solve this by mapping the property to a position in the CSV file. You can't rely on the ordering of class members in. var config = new CsvConfiguration(CultureInfo.InvariantCulture)ĬsvReader will use the position of the properties in the class as the index position. 1,oneįirst we need to tell the reader that there is no header record, using configuration. Let's say out CSV file doesn't have a header at all. You can use this function to do other things such as remove When the reader needs to find the property to set for the Both the header and the property name are ran through the Using the configuration PrepareHeaderForMatch, we're able to change how the header matching Using (var csv = new CsvReader(reader, config)) Using (var reader = new StreamReader("path\\to\\file.csv")) var config = new CsvConfiguration(CultureInfo.InvariantCulture) Just change how our properties match against the header names. We want our property names to be Pascal Case, so we can Let's say our CSV file names are a little different than our class properties and we don't want to CsvReader is forward only, so if you want to run any LINQ queriesĪgainst your data, you'll have to pull the whole file into memory. If you do anything that executes a LINQ projection, such as calling. That also means that only a small portion of the file is read into memory. What this means is that only a single record is returned at a time as you iterate the records. The GetRecords method will return an IEnumerable that will yield records. Using (var csv = new CsvReader(reader, CultureInfo.InvariantCulture)) using (var reader = new StreamReader("path\\to\\file.csv")) If our class property names match our CSV file header names, we can read the file without any configuration. Id,NameĪnd a class definition that looks like this. Let's say we have CSV file that looks like this.
If you want to read or write in a non-standard format, you canĬhange the configuration for NewLine. CsvHelper can read \r\n, \r, or \n without any configuration changes. Newlinesīy default, CsvHelper will follow RFC 4180 and use \r\n for writing newlines no matter what operating system
#Vb auto convert string to long portable#
InvariantCulture will be the most portable for writing a file and reading it back again, so that will be used in most of the examples. Choose the appropriate culture for your data. You can change the configuration of any of these too if you like. The culture is used to determine the default delimiter, default line ending, and formatting when type converting. Prerequisites CultureInfoĬsvHelper requires you to specify the CultureInfo that you want to use.
Please look over the prequisites to make sure you have an NET knowledge that is implied when using this documentation. NET CLI Console > dotnet add package CsvHelper Package Manager Console PM> Install-Package CsvHelper
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