Net streamwriter append to file

Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Ask Question. Asked 9 years, 4 months ago. Active 9 years, 4 months ago. Viewed 18k times. ReadToEnd ; sreader. WriteLine "example text" ; swriter. WriteLine str ; swriter. Close ; But it doesn't seem optimized. So is there any other way?

Hamed Hamed 1, 6 6 gold badges 21 21 silver badges 41 41 bronze badges. Writing to the start of the file will overwrite what's there. Consider appending data to the end of the file instead of the start. You'd need to read the entire file, store it in a string, then insert your new data to the beginning of that string using String.

Insert , then rewrite the entire file with the modified string. Oded I'm afraid of overwriting. Why do you need to write to the start of the file? Show 2 more comments. Active Oldest Votes. Visual Basic users may choose to use the methods and properties provided by the Log class or FileSystem class for creating or writing to log files.

Skip to main content. This browser is no longer supported. Download Microsoft Edge More info. Contents Exit focus mode. Is this page helpful? Please rate your experience Yes No. This specifies the append overload. Then The file is opened again, and a second line is appended to it. The text file contents are shown in the final comment. NET program that uses StreamWriter to append.

Here we use a For-loop with StreamWriter. When you have to loop and add text to a file, you should reuse a single StreamWriter—this improves performance. For Each, For. Write The file is opened, and one Windows file handle is created. Then, that same system resource is used to write ten numbers to the file. Format The Write call in the For-loop specifies a format string. The format string prints the Integer with one decimal place.

You need to specify the encoding of your target file in the StreamWriter constructor if it is not the default UTF8. StreamWriter in VB. NET has a few more Functions on it.