Create a new snippet from a blank template.

OfficeAtWorkDemo.WORD.yaml

name: OfficeAtWorkDemo
description: Create a new snippet from a blank template.
host: WORD
api_set: {}
script:
  content: |-
    OfficeExtension.config.extendedErrorLogging = true;
    $("#file").change(getBase64);
    $("#ok").click(() => tryCatch(run));

    let externalWorkbook;
    async function getBase64() {
      // Retrieve the file and set up an HTML FileReader element.
      const myFile = <HTMLInputElement>document.getElementById("file");
      const reader = new FileReader();
      reader.onload = (event) => {
        const startIndex = reader.result.toString().indexOf("base64,");
        externalWorkbook = reader.result.toString().substr(startIndex + 7);
      };
      // Read the file as a data URL so that we can parse the base64-encoded string.
      reader.readAsDataURL(myFile.files[0]);
    }

    async function run() {
      await Word.run(async (context) => {
        // console.log(externalWorkbook);
        const styles = context.application.retrieveStylesFromBase64(externalWorkbook);
        await context.sync();

        const jsonObject = JSON.parse(styles.value);
        console.log(jsonObject['Styles'][2].Font.Color);

        // add a new style with the same font.color as the one 
        // imported from the selected file
        const newlyAddedStyle = context.document.addStyle("OfficeAtWork_NEW_STYLE",Word.StyleType.paragraph);
        newlyAddedStyle.font.color = jsonObject['Styles'][1].Font.Color;
        await context.sync();

        // apply the imported style to curret selected range
        const range = context.document.getSelection();
        range.style = "OfficeAtWork_NEW_STYLE";
        await context.sync();

        // check if the range is the same style as the imported one just now
        const range2 = context.document.getSelection();
        range2.load();
        await context.sync();
        console.log(range2.style);
      });
    }

    /** Default helper for invoking an action and handling errors. */
    async function tryCatch(callback) {
      try {
        await callback();
      } catch (error) {
        // Note: In a production add-in, you'd want to notify the user through your add-in's UI.
        console.error(error);
      }
    }

    interface Style {
      BaseStyle: string;
      BuiltIn: boolean;
      InUse: boolean;
      Linked: boolean;
      NextParagraphStyle: string;
    }
  language: typescript
template:
  content: "<h1>Select a file to retrieve styles from</h1>\n<form>\n\t<input type=\"file\" id=\"file\"/>\n\t</form>\n\t<br>\n\t<button id=\"ok\" class=\"ms-Button\">\n\t\t\t<span class=\"ms-Button-label\">OK</span>\n\t\t</button>"
  language: html
style:
  content: |-
    section.samples {
        margin-top: 20px;
    }

    section.samples .ms-Button, section.setup .ms-Button {
        display: block;
        margin-bottom: 5px;
        margin-left: 20px;
        min-width: 80px;
    }
  language: css
libraries: |
  https://appsforoffice.microsoft.com/lib/beta/hosted/office.js
  @types/office-js-preview

  office-ui-fabric-js@1.4.0/dist/css/fabric.min.css
  office-ui-fabric-js@1.4.0/dist/css/fabric.components.min.css

  core-js@2.4.1/client/core.min.js
  @types/core-js

  jquery@3.1.1
  @types/jquery@3.3.1