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Services / Excel Services / Merge Excel Service / Merge Multiple Excel Files Posted from Client
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    Merge Multiple Excel Files Posted from Client
    In This Topic

    This section demonstrates how to call the Web API service through a client application and merge multiple excel files, that are posted from client, into workbook.

    Step 1: Call the Service

    Step 2: Run the Client Project

    The following example makes a call to the Web API service through HTML as well as WinForms client applications. These clients send a POST request to the service, which returns a response stream. This response stream is then saved in the desired excel file format.

    In the following example, user provides the excel files (to merge into workbook) through the client applications. Moreover, the end user needs to specify the service URL, name and desired file format of workbook (generated upon merging multiple excel sheets) through client project. It is so, because the parameters or query string for merging excel are sent in the HTTP message body of the POST request and not in the request URL.

    Note: Service can merge xls, xlsx, and csv files posted from the client.

    Step 1: Call the Service

    Complete the following steps to call the Web API service.

    1. Create a WinForms application, as discussed in Configure Client for REST API service. Add four C1Label, three C1TextBox, two C1Button controls and an OpneFileDialog component. Set their text properties so that your form appears as shown below.
    2. Add the following code on button-click event of "Select Files to Merge" button.
      C#
      Copy Code 
      private void button1_Click(object sender, EventArgs e) {
  OpenFileDialog x = new OpenFileDialog();
  x.Multiselect = true;
  x.ShowDialog();
  result = x.FileNames;
  label1.Text = "Files Selected";
}

    3. Add the following code on button-click event of "Merge Excel" button.
      C#
      Copy Code 
      private void button2_Click(object sender, EventArgs e) {
  if (result.Length & lt; = 0) {
    MessageBox.Show("Please select excel files to merge.");
    return;
  }
  using(var client = new HttpClient())
  using(var formData = new MultipartFormDataContent())
  using(var fileStream = File.OpenRead(result[0])) {
    using(var fileStream1 = File.OpenRead(result[1])) {
      var fileName = string.IsNullOrEmpty(txtFileName.Text) ? "test" : txtFileName.Text;
      var fileFormat = string.IsNullOrEmpty(txtFileFormat.Text) ? "xlsx" : txtFileFormat.Text;
      formData.Add(new StringContent(fileName), "FileName");
      formData.Add(new StringContent(fileFormat), "Type");
      formData.Add(new StreamContent(fileStream), "filesToMerge", result[0]);
      formData.Add(new StreamContent(fileStream1), "filesToMerge", result[1]);
      var response = client.PostAsync(txtUrl.Text, formData).Result;
      if (!response.IsSuccessStatusCode) {
        MessageBox.Show("Get invalid response.");
        return;
      }
      var tempPath = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString());
      if (!Directory.Exists(tempPath)) {
        Directory.CreateDirectory(tempPath);
      }
      var tempFilePath = Path.Combine(tempPath, string.Format("{0}.{1}", fileName, fileFormat));
      using(var newFile = File.Create(tempFilePath)) {
        response.Content.ReadAsStreamAsync().Result.CopyTo(newFile);
      }
      Process.Start(tempFilePath);
    }
  }
}

      Note that for POST request, formData is used, which is an instance of System.Net.Http.MultipartFormDataContent class. Through code, we add HTTP content to formData and pass it while sending asynchronous POST request to the specified uri.

    1. Create an HTML application, as discussed in Configure Client for REST API service.
    2. Add the following markups in the <form> tags, within <body> tags, of your HTML page.
      HTML
      Copy Code 
      <form action="https://demos.componentone.com/ASPNET/5/C1WebAPI/3.0.20193.222/api/excel/merge" method="POST" enctype="multipart/form-data">
        <label for="FilesToMerge">Excel Files to Merge:</label>
    <input type="file" id="FilesToMerge" name="FilesToMerge" multiple/>
    <br /><br />
    <label for="FileName">Merged Workbook Name:</label>
    <input type="text" id="fileName" name="FileName" value="Excel"/>
    <br /><br />
    <label for="Type">Generated File Format:</label>
    <input type="text" id="Type" name="Type" value="xlsx" />
    <br /><br />
    <input type="submit" value="Merge Excel"/>
</form>

      Note that, for POST request we set method attribute of <form> tag to POST, its enctype attribute to "multipart/form-data" and set its action attribute to service request URL. Also, we create input controls on the HTML page, which take various parameters to merge multiple excel files, provided by client, to the desired workbook format.

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    Step 2: Run the Client Project

    WinForms Application

    HTML Application

    Explore detailed demo samples of REST API service to merge multiple excel files at:

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