Read a large Text File ( 250 MB) And Write in TextBox C#

Rahul Singh

8y9kLearn iOS Programming

i am Working on a Project on tech asp.net C#

I Have a Notepad file almost 250 MB i want to Write its Text on TextBox

I used this Code but it taking too much time at last Throwing error

OutOfMemoryException

any one can suggest me what is the Easiest way.

Here is the Code Below.

StringBuilder fileText = new StringBuilder();

using (FileStream fs = File.Open(FilePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))

using (BufferedStream bs = new BufferedStream(fs))

using (StreamReader sr = new StreamReader(bs))

{

string line = "";

txtReader.Text = "";

while ((line = sr.ReadLine()) != null)

{

//fileText.AppendLine(line);

txtReader.Text += line.ToString();

}

txtReader.Text = fileText.ToString();

7 Replies

Know the answer? Post it — somebody with the same question will find it here.

Manav Pandya8y ago
Hello

You can do as per BufferedStream , can specify size you want

Without trying you can not judge .

Thank you should use RichTextBox instead textbox

Following post may help you :

https://msdn.microsoft.com/en-us/library/system.windows.forms.richtextbox.loadfile.aspx
http://www.dreamincode.net/forums/topic/343670-loading-large-text-files-in-a-richtextbox-outofmemoryexception/

https://www.codeproject.com/Questions/101293/Import-of-txt-file-into-textbox

Thanks
+1
Rahul Singh8y ago
I Already used this code. see my link below i given a same code which thrown error of out of memory execption. because file size is large.
@Manav
0
Amit Gupta8y ago
Hey

Have you tried using async/await processing, it will not freeze your UI and able to perform the task smoother

Update:
You can also use richtextbox control and load the file
+1
Manav Pandya8y ago
Try following snippet :
using (FileStream fs = File.Open(path, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
{
    using (BufferedStream bs = new BufferedStream(fs))
    {
        using (StreamReader sr = new StreamReader(bs))
        {
            string line;
            while ((line = sr.ReadLine()) != null)
            {

            }
        }
    }
}
Thanks
-1
Rahul Singh8y ago
File size is too large

@Manav Your Code is not working
+1
Sagar Pandurang Kap8y ago
Hi,
try below code :-

using System;
using System.IO;
namespace csharp_station.howto
{
class TextFileReader
{
static void Main(string[] args)
{
// create reader & open file
Textreader tr = new StreamReader("date.txt");
// read a line of text
Console.WriteLine(tr.ReadLine());
// close the stream
tr.Close();
}
}
}

Hope it helps...
-3
Manav Pandya8y ago
Hello

You can try as following snippet :
// Select your file and load data inside textbox

textbox1.Text = File.ReadAllText(filedialog.FileName);
Still you need any help , let me know
For more batter help , and two way reading of text file find following link :

https://social.msdn.microsoft.com/Forums/vstudio/en-US/b41e6115-f19e-4be2-be7e-f2fcd80dc64d/how-do-i-save-the-text-in-textbox-to-text-file-and-then-read-it-back-and-add-the-text-in-the-textbox?forum=csharpgeneral

Thanks
-2