Tag Archives: web

Continuously graph stock prices in C#

The example Get stock prices from the internet in C# explains how to get stock prices from the Yahoo! finance web site. This example uses similar techniques to query the site periodically and then graph stock prices. This example is … Continue reading

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Make an HTML table of thumbnail images in C#

The post Make thumbnails and a web page to display the images in a directory in C# shows how to make thumbnails for the images in a directory and then build a web page to display them. There are lots … Continue reading

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Make thumbnails and a web page to display the images in a directory in C#

This example searches a directory and makes thumbnails for each of the image files it finds there. It also builds a web page that displays the thumbnails and that includes links to the full-scale images. It puts all of the … Continue reading

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Make CAPTCHA images with overlapping characters in C#

The following MakeCaptchaImage2 method creates a Bitmap containing a CAPTCHA image. private Random Rand = new Random(); // Draw the words with letters overlapping each other. private Bitmap MakeCaptchaImage2(string txt, int wid, int hgt, Font the_font, Brush the_brush) { Bitmap … Continue reading

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Make CAPTCHA images in C#

CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) images are those distorted pictures of words that some Web sites make you enter to prove you are a human and not an automated process. The idea is … Continue reading

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Get file size and last modification time on an FTP server in C#

The FtpGetFileSize method shown in the following code gets a file’s size in bytes. The uri parameter gives the full path to the file as in ftp://www.somewhere.com/test.txt. Note that the URI must begin with ftp not http. // Use FTP … Continue reading

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Upload files to an FTP server in C#

The following FtpUploadFile method uploads a file to an FTP server. The to_uri parameter is a URI (Uniform Resource Identifier) that identifies the target file as in ftp://www.somewhere.com/test.txt. The other parameters are self-explanatory. // Use FTP to upload a file. … Continue reading

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Upload text into a file on an FTP server in C#

The following FtpUploadString method uploads a text string into a file on an FTP server. The to_uri parameter is a URI (Uniform Resource Identifier) that identifies the target file as in ftp://www.somewhere.com/test.txt. The other parameters are self-explanatory. // Use FTP … Continue reading

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Graph stock prices downloaded from the internet in C#

This example uses techniques described in other examples to graph stock prices downloaded from the internet. it’s based on these two examples: Get stock prices from the internet in C# Draw a labeled line graph that displays value tooltips in … Continue reading

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Get stock prices from the internet in C#

There are many web sites that can return stock prices to a program. This program uses download.finance.yahoo.com. It builds a URL of the following form to get prices for MCI, DIS, COKE, and PEP: http://download.finance.yahoo.com/d/quotes.csv?s=MCI+DIS+COKE+PEP&f=sl1d1t1c1 The end of the URL, … Continue reading

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