ReadLines method with System. Here's how:. All we are doing here is run the method once for each of our input files remembering to clear the cache before each run and output the time taken as well as the number of times GC kicked in across all generations. Well, the System. Count extension method on File. ReadLines returns an Int32 which has a max value of 2,,, and as we saw earlier, there are over 3 billion lines in the 5. Also notice the number of GCs that took place, we didn't have any Gen2 collection and that's mainly due to the fact that we don't need to hold on to each line read from the file so nothing survives the Gen1 collection but even without the expensive Gen2 collection we are still causing Gen0 and Gen1 which are both blocking operations requiring all user threads to be suspended.
Let's first fix that OverflowException. You may have realised that we should have used the System. LongCount as opposed to System. Count on, so why don't we do that ourselves this time avoiding the OverflowException :. Again nothing really complicated here, we have the lineCounter declared as Int64 which we then increment every time a line is read from the reader.
Okay, let's benchmark it:. The results are almost identical albeit slightly faster compared to the LINQ version but this time we managed to handle the 5. So can we do better? Is there a way to count the lines without allocating anything on the heap so that GC doesn't have to run?
Sounds pretty easy but before jumping to the implementation let's remember that there are 3 different flavors of end-of-line characters:. Take your time to study what it actually does but all it is doing is incrementing a counter whenever it sees an end-of-line character. Now that we have a working algorithm why don't we also sprinkle some C 7 goodness over it!
We can rewrite the body of the for loop as a switch statement with some pattern matching case blocks. You can read more about this feature HERE. In terms of readability, both versions look pretty similar but which one should we pick? Is there any performance difference between the two versions? Let's take our dotTrace profiler for a spin. Chain with Remove chain. Remove no tools? This tool cannot be chained. Text line counter options Counter Options Count All Lines Find the number of all lines in the text, including empty lines.
Count Non-empty Lines Find the number of lines that have at least one character in them. Count Empty Lines Find the number of empty lines. Trimmer Options Trim Lines Remove extra spaces and tabs from both ends of each line. This option helps to get rid of lines that consist only of spaces and tabs. Text line counter tool What is a text line counter? With this online tool, you can calculate the number of lines in the given text.
The first one counts absolutely all lines, including the empty lines with no characters in them. The second one ignores the empty lines and counts lines that have visible characters in them. The third one finds the number of all blank lines.
There are situations when the line seems empty but actually contains one or more invisible space and tab symbols. In this case, you can use the "Trim Lines" option, which will remove leading and trailing whitespaces and turn them into empty lines.
Text line counter examples Click to use. List of Brands. In this example, we paste a list of world-famous brands in the input and count the number of lines in it.
We count absolutely all text rows, including empty ones and get a total amount of 12 rows. Required options These options will be used automatically if you select this example.
Count All Lines Find the number of all lines in the text, including empty lines. World's Largest Lakes. In this example, we activate the "Count Non-empty Lines" mode and process a text file with the largest lakes in the world. In this mode, the tool ignores all empty lines and shows that there are only 7 lines with actual lake names.
Invisible Blank Lines. This example loads 17 text lines with drink names in the input and many of these lines are seemingly blank. If you load this example and select the text, you'll see that these lines are actually not completely empty.
They contain invisible spaces and tabs characters. Not to mislead us when counting lines, we have activated the "Trim Lines" option, which removes all whitespaces from the lines and shows the true number of textual lines. Trim Lines Remove extra spaces and tabs from both ends of each line. Number of Empty Lines. In this example, we count the number of blank lines in a list of birds. We enable the "Trim Lines" mode to remove all whitespace characters from the beginning and end of each line.
This makes sure that lines that have accidental spaces on them don't get counted. Pro tips Master online text tools.
You can pass input to this tool via? Here's how to type it in your browser's address bar. Click to try! All text tools. Didn't find the tool you were looking for? Let us know what tool we are missing and we'll build it! Split Text. Quickly split text into chunks. Join Text.
Quickly merge lines of text together via a delimiter. Repeat Text. Quickly repeat text many times. Reverse Text. Quickly write text backwards. Truncate Text. Quickly cut text to the given length. Trim Text. Quickly trim left or right side of text. Left-pad Text. Quickly pad the left side of text. Right-pad Text. Quickly pad the right side of text.
Right-align Text. Quickly align text to the right side. Center Text. Add a Prefix to Text. Quickly prepend a prefix to text. Add a Suffix to Text. Quickly append a suffix to text. Remove All Empty Lines. Quickly delete all blank lines from text. Remove All Duplicate Lines. Quickly delete all repeated lines from text. Filter Text Lines. Quickly return text lines that match a string or a regex. Extract a Text Fragment. Quickly extract a text snippet of the given length. Find and Replace Text.
Quickly find and replace text patterns. Find the Length of Text. Quickly count the number of characters in text. Count Text Lines.
Quickly find the number of lines in text. Add Line Numbers. Quickly add a number before every text line. Create an Image from Text. Quickly create an image from text. Generate Zalgo Text. Apply the Zalgo effect to the input text. Create a Palindrome. Quickly construct a palindrome from plain text. Check if Text is a Palindrome. Quickly test if text is a palindrome. Change Text Case. Quickly switch between various letter cases in text. Convert Text to Uppercase.
Quickly convert text letters to uppercase. Convert Text to Lowercase. Quickly convert text letters to lowercase. Randomize Text Case. Quickly randomize character case in text. Invert Text Case. Quickly invert character case in text. Convert Spaces to Newlines. Quickly replace spaces with newlines in text.
Convert Newlines to Spaces. Quickly replace newlines with spaces in text. Convert Spaces to Tabs. Quickly get tabs instead of spaces in text. Convert Tabs to Spaces. Quickly get spaces instead of tabs in text. Remove All Whitespace. Quickly clear text from spaces, tabs, and newlines.
Remove All Punctuation. Quickly clear text from dots, commas, and similar characters. Quickly extract tag content from HTML code. Extract Text from XML. Quickly extract tag content from an XML document. Extract Text from BBCode. Quickly extract all textual data from BBCode markup.
Quickly extract keys and values from a JSON data structure. Quickly convert text to a JSON string. Quickly convert previously JSON stringified text to plain text. Slash-escape Text.
Quickly escape special symbols in text with slashes. Slash-unescape Text. Quickly remove slashes from previously slash-escaped text. ROT13 Text. Quickly encode or decode text using ROT13 cipher algorithm. ROT47 Text. Quickly encode and decode text with ROT47 cipher algorithm. Likewise, if you want to count the number of lines in single or multiple files, you can use different commands.
You can use "-l" or "--line" option with wc command as follows:. You can see that wc also counts the blank line and print the number of lines along with the filename.
Moreover, to display a number of lines from more than one file at the same time, you need to pass the filenames as arguments separated by space. In another way, you can also make use of the cat command to redirect the file content to the wc command as input via pipe ' '.
Though it will also count the number of lines in a file, here the use of cat seems redundant. Awk is a very powerful command-line utility for text processing. If you already know awk , you can use it for several purposes including counting the number of lines in files. Hence, if you just want to use it to count the total number of lines in a file, you can remember the following command:. Sed is a also very useful tool for filtering and editing text. More than a text stream editor, you can also use sed for counting the number of lines in a file using the command:.
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