## ColumnCollection class

Collection of the [Column](../column/) objects that represent the individual column(setting)s in a worksheet. The Column object only represents the settings such as column width, styles, .etc. for the whole column, has nothing to do with the fact that there are non-empty cells(data) or not in corresponding column. And the "Count" of this collection only represents the count Column objects that have been instantiated in this collection, has nothing to do with the fact that there are non-empty cells(data) or not in the worksheet.

```javascript
class ColumnCollection;
```


### Example
```javascript
const { Workbook, Color, BackgroundType, StyleFlag, SaveFormat } = AsposeCells;

//Instantiating a Workbook object
var workbook = new Workbook();
//Obtaining the reference of the first worksheet
var worksheet = workbook.worksheets.get(0);
//Add new Style to Workbook
var style = workbook.createStyle();
//Setting the background color to Blue
style.foregroundColor = Color.Blue;
//setting Background Pattern
style.pattern = BackgroundType.Solid;
//New Style Flag
var styleFlag = new StyleFlag();
//Set All Styles
styleFlag.all = true;

//Change the default width of first ten columns
for (var i = 0; i < 10; i++) {
    worksheet.cells.columns.get(i).width = 20;
}

//Get the Column with non default formatting
var columns = worksheet.cells.columns;
var count = columns.count;
for (var i = 0; i < count; i++) {
    var column = columns.getColumnByIndex(i);
    //Apply Style to first ten Columns
    column.applyStyle(style, styleFlag);
}

//Saving the Excel file
var uint8Array = workbook.save(SaveFormat.Xlsx);
```
## Methods

| Method | Description |
| --- | --- |
| [get(number)](#get-number-)| Gets a [Column](../column/) object by column index. The Column object of given column index will be instantiated if it does not exist before. |
| [getColumnByIndex(number)](#getColumnByIndex-number-)| Gets the [Column](../column/) object by the position in the list. |


### get(number) {#get-number-}

Gets a [Column](../column/) object by column index. The Column object of given column index will be instantiated if it does not exist before.

```javascript
get(columnIndex: number) : Column;
```

**Parameters:**
| Parameter | Type | Description |
| --- | --- | --- |
| columnIndex | number |  |

**Returns**

[Column](../column/)

### getColumnByIndex(number) {#getColumnByIndex-number-}

Gets the [Column](../column/) object by the position in the list.

```javascript
getColumnByIndex(index: number) : Column;
```

**Parameters:**
| Parameter | Type | Description |
| --- | --- | --- |
| index | number | The position in the list. |

**Returns**

Returns the column object.