excel.charttrendlinecollection.yml

### YamlMime:TSType
name: Excel.ChartTrendlineCollection
uid: 'excel!Excel.ChartTrendlineCollection:class'
package: excel!
fullName: Excel.ChartTrendlineCollection
summary: Represents a collection of chart trendlines.
remarks: '\[ [API set: ExcelApi 1.7](/javascript/api/requirement-sets/excel/excel-api-requirement-sets) \]'
isPreview: false
isDeprecated: false
type: class
properties:
  - name: context
    uid: 'excel!Excel.ChartTrendlineCollection#context:member'
    package: excel!
    fullName: context
    summary: >-
      The request context associated with the object. This connects the add-in's process to the Office host
      application's process.
    remarks: ''
    isPreview: false
    isDeprecated: false
    syntax:
      content: 'context: RequestContext;'
      return:
        type: '<xref uid="excel!Excel.RequestContext:class" />'
  - name: items
    uid: 'excel!Excel.ChartTrendlineCollection#items:member'
    package: excel!
    fullName: items
    summary: Gets the loaded child items in this collection.
    remarks: ''
    isPreview: false
    isDeprecated: false
    syntax:
      content: 'readonly items: Excel.ChartTrendline[];'
      return:
        type: '<xref uid="excel!Excel.ChartTrendline:class" />[]'
methods:
  - name: add(type)
    uid: 'excel!Excel.ChartTrendlineCollection#add:member(1)'
    package: excel!
    fullName: add(type)
    summary: Adds a new trendline to trendline collection.
    remarks: >-
      \[ [API set: ExcelApi 1.7](/javascript/api/requirement-sets/excel/excel-api-requirement-sets) \]


      #### Examples


      ```TypeScript

      // Link to full sample:
      https://raw.githubusercontent.com/OfficeDev/office-js-snippets/prod/samples/excel/10-chart/chart-trendlines.yaml


      await Excel.run(async (context) => {
          const sheet = context.workbook.worksheets.getItem("Sample");

          let seriesCollection = sheet.charts.getItemAt(0).series;

           // Add a trendline.  
          seriesCollection.getItemAt(0).trendlines.add("Linear");

          await context.sync();
      });

      ```
    isPreview: false
    isDeprecated: false
    syntax:
      content: 'add(type?: Excel.ChartTrendlineType): Excel.ChartTrendline;'
      parameters:
        - id: type
          description: Specifies the trendline type. The default value is "Linear". See `Excel.ChartTrendline` for details.
          type: '<xref uid="excel!Excel.ChartTrendlineType:enum" />'
      return:
        type: '<xref uid="excel!Excel.ChartTrendline:class" />'
        description: ''
  - name: add(typeString)
    uid: 'excel!Excel.ChartTrendlineCollection#add:member(2)'
    package: excel!
    fullName: add(typeString)
    summary: Adds a new trendline to trendline collection.
    remarks: '\[ [API set: ExcelApi 1.7](/javascript/api/requirement-sets/excel/excel-api-requirement-sets) \]'
    isPreview: false
    isDeprecated: false
    syntax:
      content: >-
        add(typeString?: "Linear" | "Exponential" | "Logarithmic" | "MovingAverage" | "Polynomial" | "Power"):
        Excel.ChartTrendline;
      parameters:
        - id: typeString
          description: Specifies the trendline type. The default value is "Linear". See `Excel.ChartTrendline` for details.
          type: '"Linear" | "Exponential" | "Logarithmic" | "MovingAverage" | "Polynomial" | "Power"'
      return:
        type: '<xref uid="excel!Excel.ChartTrendline:class" />'
        description: ''
  - name: getCount()
    uid: 'excel!Excel.ChartTrendlineCollection#getCount:member(1)'
    package: excel!
    fullName: getCount()
    summary: Returns the number of trendlines in the collection.
    remarks: '\[ [API set: ExcelApi 1.7](/javascript/api/requirement-sets/excel/excel-api-requirement-sets) \]'
    isPreview: false
    isDeprecated: false
    syntax:
      content: 'getCount(): OfficeExtension.ClientResult<number>;'
      return:
        type: '<xref uid="office!OfficeExtension.ClientResult:class" />&lt;number&gt;'
        description: ''
  - name: getItem(index)
    uid: 'excel!Excel.ChartTrendlineCollection#getItem:member(1)'
    package: excel!
    fullName: getItem(index)
    summary: 'Gets a trendline object by index, which is the insertion order in the items array.'
    remarks: '\[ [API set: ExcelApi 1.7](/javascript/api/requirement-sets/excel/excel-api-requirement-sets) \]'
    isPreview: false
    isDeprecated: false
    syntax:
      content: 'getItem(index: number): Excel.ChartTrendline;'
      parameters:
        - id: index
          description: Represents the insertion order in the items array.
          type: number
      return:
        type: '<xref uid="excel!Excel.ChartTrendline:class" />'
        description: ''
  - name: load(options)
    uid: 'excel!Excel.ChartTrendlineCollection#load:member(1)'
    package: excel!
    fullName: load(options)
    summary: >-
      Queues up a command to load the specified properties of the object. You must call `context.sync()` before reading
      the properties.
    remarks: ''
    isPreview: false
    isDeprecated: false
    syntax:
      content: >-
        load(options?: Excel.Interfaces.ChartTrendlineCollectionLoadOptions & Excel.Interfaces.CollectionLoadOptions):
        Excel.ChartTrendlineCollection;
      parameters:
        - id: options
          description: Provides options for which properties of the object to load.
          type: >-
            <xref uid="excel!Excel.Interfaces.ChartTrendlineCollectionLoadOptions:interface" /> & <xref
            uid="excel!Excel.Interfaces.CollectionLoadOptions:interface" />
      return:
        type: '<xref uid="excel!Excel.ChartTrendlineCollection:class" />'
        description: ''
  - name: load(propertyNames)
    uid: 'excel!Excel.ChartTrendlineCollection#load:member(2)'
    package: excel!
    fullName: load(propertyNames)
    summary: >-
      Queues up a command to load the specified properties of the object. You must call `context.sync()` before reading
      the properties.
    remarks: ''
    isPreview: false
    isDeprecated: false
    syntax:
      content: 'load(propertyNames?: string | string[]): Excel.ChartTrendlineCollection;'
      parameters:
        - id: propertyNames
          description: A comma-delimited string or an array of strings that specify the properties to load.
          type: 'string | string[]'
      return:
        type: '<xref uid="excel!Excel.ChartTrendlineCollection:class" />'
        description: ''
  - name: load(propertyNamesAndPaths)
    uid: 'excel!Excel.ChartTrendlineCollection#load:member(3)'
    package: excel!
    fullName: load(propertyNamesAndPaths)
    summary: >-
      Queues up a command to load the specified properties of the object. You must call `context.sync()` before reading
      the properties.
    remarks: ''
    isPreview: false
    isDeprecated: false
    syntax:
      content: 'load(propertyNamesAndPaths?: OfficeExtension.LoadOption): Excel.ChartTrendlineCollection;'
      parameters:
        - id: propertyNamesAndPaths
          description: >-
            `propertyNamesAndPaths.select` is a comma-delimited string that specifies the properties to load, and
            `propertyNamesAndPaths.expand` is a comma-delimited string that specifies the navigation properties to load.
          type: '<xref uid="office!OfficeExtension.LoadOption:interface" />'
      return:
        type: '<xref uid="excel!Excel.ChartTrendlineCollection:class" />'
        description: ''
  - name: toJSON()
    uid: 'excel!Excel.ChartTrendlineCollection#toJSON:member(1)'
    package: excel!
    fullName: toJSON()
    summary: >-
      Overrides the JavaScript `toJSON()` method in order to provide more useful output when an API object is passed to
      `JSON.stringify()`<!-- -->. (`JSON.stringify`<!-- -->, in turn, calls the `toJSON` method of the object that is
      passed to it.) Whereas the original `Excel.ChartTrendlineCollection` object is an API object, the `toJSON` method
      returns a plain JavaScript object (typed as `Excel.Interfaces.ChartTrendlineCollectionData`<!-- -->) that contains
      an "items" array with shallow copies of any loaded properties from the collection's items.
    remarks: ''
    isPreview: false
    isDeprecated: false
    syntax:
      content: 'toJSON(): Excel.Interfaces.ChartTrendlineCollectionData;'
      return:
        type: '<xref uid="excel!Excel.Interfaces.ChartTrendlineCollectionData:interface" />'
        description: ''
extends: '<xref uid="office!OfficeExtension.ClientObject:class" />'