User Guide - .Net

• User Guide - .Net
  • Requirements
  • Installation
  • Build Your First Application
    • Create a New Project
    • Include the Label Recognizer library
    • Initialize the Label Recognizer
    • Recognition Process and How to Use the Results
    • Build and Run the Project

Requirements

• Operating systems:
  • Windows: 7, 8, 10, 2003, 2008, 2008 R2, 2012.

• Environment: Visual Studio 2008 and above.

• Framework supported: .NET Framework 2.0, .NET Framework 4.0

Installation

If you don’t have SDK yet, please go to Dynamsoft website to get it. After the sdk is decompressed, the root directory of the DLR installation package is DynamsoftLabelRecognizer, which is represented by [INSTALLATION FOLDER].

Build Your First Application

Let’s start by creating a console application which demonstrates how to use the minimum code to recognize text from an image file.

You can download the similar complete source code from Here.

Create a New Project

1. Open Visual Studio. Go to File > New > Project, select Visual C# template, create a new Console Application (.NET Framework) named DLRCSharpSample.

Include the Label Recognizer library

1. Add the Dynamsoft Label Recognizer libraries (Dynamsoft.LabelRecognizer.dll and Dynamsoft.Core.dll) to the project references. The lib files can be found in [INSTALLATION FOLDER]\Lib\[dotNetVersion].

   Note: Select the corresponding folder (2.0 or 4.0) based on your project’s .NET Framework version.

2. Import the namespace in the file Program.cs

    using Dynamsoft.DLR;
   

Initialize the Label Recognizer

1. Initialize the license key

    // 1.Initialize license.
    LabelRecognizer.InitLicense("DLS2eyJvcmdhbml6YXRpb25JRCI6IjIwMDAwMSIsInByb2R1Y3RzIjoyfQ==");
   

   Note:

   • Network connection is required for the license to work.
   • “DLS2***” is a default free public trial license used in the sample.
   • You can request a 30-day trial license via the Request a Trial License link.

2. Create an instance of Dynamsoft Label Recognizer

    // 2.Create an instance of Label Recognizer.
    LabelRecognizer dlr = new LabelRecognizer();
   

Recognition Process and How to Use the Results

1. Recognizing text in an image

    DLR_Result[] results = null;
   
    try
    {
        // 3.Recognize text from an image file.
        results = dlr.RecognizeByFile("../../SampleImages/dlr-sample-vin.png", "");
    }
    catch (LabelRecognizerException exp)
    {
        Console.WriteLine(exp);
    }
   

   You can download the image dlr-sample-vin.png for testing. In addition, you can replace it with the full path of the image you want to recognize.

   For the error handling mechanism, when an error occurs during the recognition process, an exception will be thrown. You should add codes for error handling based on your needs. Check out Error Code for full supported error codes.

2. Get and output the recognition results

    if (results != null && results.Length > 0)
    {
        for (int i = 0; i < results.Length; ++i)
        {
            Console.WriteLine("Result " + i.ToString() + ":");
   
            // Get result of each text area (also called label).
            DLR_Result result = results[i];
            for (int j = 0; j < result.LineResults.Length; ++j)
            {
                // Get the result of each text line in the label.
                DLR_LineResult lineResult = result.LineResults[j];
                Console.WriteLine(">>LineResult " + j.ToString() + ": " + lineResult.Text);
            }
        }
    }
    else
    {
        Console.WriteLine("No data detected.\n");
    }
   

   The recognition results of SDK are organized into a four-tier structure:

   • DLR_Result[] corresponds to the results of an image
   • DLR_Result corresponds to the result of a TextArea (also called Label)
   • DLR_LineResult corresponds to the result of each TextLine in the Label
   • DLR_CharacterResult corresponds to the result of each Character in the TextLine

   The structure is shown in the figure below:

   

   Figure 1 – DLR Result Structure

You can download the similar complete source code from Here.

Build and Run the Project

1. Build the application through Visual Studio and copy the related folders to the same folder as the EXE file. The related folders includes [INSTALLATION FOLDER]\Lib\[dotNetVersion]\x86 and [INSTALLATION FOLDER]\Lib\[dotNetVersion]\x64.

   Note: Select the corresponding folder (2.0 or 4.0) based on your project’s .NET Framework version.

2. Run the program DLRCSharpSample.exe.