in viewDidLoad() {    

   tableView.separatorStyle = UITableViewCellSeparatorStyle.None 

}

在Swift 3, Swift 4和Swift 5中，你可以像这样写一个UITableViewCell扩展:

extension UITableViewCell {
  func separator(hide: Bool) {
    separatorInset.left = hide ? bounds.size.width : 0
  }
}

然后你可以这样使用它(当cell是你的cell实例时):

cell.separator(hide: false) // Shows separator 
cell.separator(hide: true) // Hides separator

将表格视图单元格的宽度赋为左插入值比赋给它一些随机数更好。因为在某些屏幕尺寸中，也许不是现在，但将来你的分隔符仍然是可见的因为这个随机数可能不够。此外，在iPad横屏模式下，你不能保证你的分隔符总是不可见。

在使用iOS 8.4的Swift中:

/*
    Tells the delegate that the table view is about to draw a cell for a particular row. (optional)
*/
override func tableView(tableView: UITableView,
                        willDisplayCell cell: UITableViewCell,
                        forRowAtIndexPath indexPath: NSIndexPath)
{
    if indexPath.row == 3 {
        // Hiding separator line for only one specific UITableViewCell
        cell.separatorInset = UIEdgeInsetsMake(0, cell.bounds.size.width, 0, 0)
    }
}

Note: this snippet above will work on UITableView using dynamic cells. The only problem that you can encounter is when you use static cells with categories, a separator type different than none and a grouped style for the table view. In fact, in this particular case it will not hide the last cell of each category. For overcoming that, the solution that I found was to set the cell separator (through IB) to none and then creating and adding manually (through code) your line view to each cell. For an example, please check the snippet below:

/*
Tells the delegate that the table view is about to draw a cell for a particular row. (optional)
*/
override func tableView(tableView: UITableView,
    willDisplayCell cell: UITableViewCell,
    forRowAtIndexPath indexPath: NSIndexPath)
{
    // Row 2 at Section 2
    if indexPath.row == 1 && indexPath.section == 1 {
        // Hiding separator line for one specific UITableViewCell
        cell.separatorInset = UIEdgeInsetsMake(0, cell.bounds.size.width, 0, 0)

        // Here we add a line at the bottom of the cell (e.g. here at the second row of the second section).
        let additionalSeparatorThickness = CGFloat(1)
        let additionalSeparator = UIView(frame: CGRectMake(0,
            cell.frame.size.height - additionalSeparatorThickness,
            cell.frame.size.width,
            additionalSeparatorThickness))
        additionalSeparator.backgroundColor = UIColor.redColor()
        cell.addSubview(additionalSeparator)
    }
}

更简单、更符合逻辑的做法是:

- (UIView *)tableView:(UITableView *)tableView viewForFooterInSection:(NSInteger)section
{
    return [[UIView alloc] initWithFrame:CGRectZero];
}

在大多数情况下，您不希望只看到最后一个表视图单元格分隔符。这种方法只删除了最后一个表格视图单元格分隔符，你不需要考虑自动布局问题(即旋转设备)或硬编码值来设置分隔符嵌入。

在iOS9上，我有一个问题，改变分隔符插入也会影响文本和细节标签的定位。

我用这个解出来了

override func layoutSubviews() {
    super.layoutSubviews()

    separatorInset = UIEdgeInsets(top: 0, left: layoutMargins.left, bottom: 0, right: width - layoutMargins.left)
}

实现这一点的最好方法是关闭默认的行分隔符，子类UITableViewCell，并添加一个自定义的行分隔符作为contentView的子视图-参见下面的自定义单元格，用于表示一个SNStock类型的对象，它有两个字符串属性，ticker和name:

import UIKit

private let kSNStockCellCellHeight: CGFloat = 65.0
private let kSNStockCellCellLineSeparatorHorizontalPaddingRatio: CGFloat = 0.03
private let kSNStockCellCellLineSeparatorBackgroundColorAlpha: CGFloat = 0.3
private let kSNStockCellCellLineSeparatorHeight: CGFloat = 1

class SNStockCell: UITableViewCell {

  private let primaryTextColor: UIColor
  private let secondaryTextColor: UIColor

  private let customLineSeparatorView: UIView

  var showsCustomLineSeparator: Bool {
    get {
      return !customLineSeparatorView.hidden
    }
    set(showsCustomLineSeparator) {
      customLineSeparatorView.hidden = !showsCustomLineSeparator
    }
  }

  var customLineSeparatorColor: UIColor? {
   get {
     return customLineSeparatorView.backgroundColor
   }
   set(customLineSeparatorColor) {
     customLineSeparatorView.backgroundColor = customLineSeparatorColor?.colorWithAlphaComponent(kSNStockCellCellLineSeparatorBackgroundColorAlpha)
    }
  }

  required init(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
  }

  init(reuseIdentifier: String, primaryTextColor: UIColor, secondaryTextColor: UIColor) {
    self.primaryTextColor = primaryTextColor
    self.secondaryTextColor = secondaryTextColor
    self.customLineSeparatorView = UIView(frame:CGRectZero)
    super.init(style: UITableViewCellStyle.Subtitle, reuseIdentifier:reuseIdentifier)
    selectionStyle = UITableViewCellSelectionStyle.None
    backgroundColor = UIColor.clearColor()

    contentView.addSubview(customLineSeparatorView)
    customLineSeparatorView.hidden = true
  }

  override func prepareForReuse() {
    super.prepareForReuse()
    self.showsCustomLineSeparator = false
  }

  // MARK: Layout

  override func layoutSubviews() {
    super.layoutSubviews()
    layoutCustomLineSeparator()
  }

  private func layoutCustomLineSeparator() {
    let horizontalPadding: CGFloat = bounds.width * kSNStockCellCellLineSeparatorHorizontalPaddingRatio
    let lineSeparatorWidth: CGFloat = bounds.width - horizontalPadding * 2;
    customLineSeparatorView.frame = CGRectMake(horizontalPadding,
      kSNStockCellCellHeight - kSNStockCellCellLineSeparatorHeight,
      lineSeparatorWidth,
      kSNStockCellCellLineSeparatorHeight)
  }

  // MARK: Public Class API

  class func cellHeight() -> CGFloat {
    return kSNStockCellCellHeight
  }

  // MARK: Public API

  func configureWithStock(stock: SNStock) {
    textLabel!.text = stock.ticker as String
    textLabel!.textColor = primaryTextColor
    detailTextLabel!.text = stock.name as String
    detailTextLabel!.textColor = secondaryTextColor
    setNeedsLayout()
  } 
}

要禁用默认的行分隔符，请使用tableView。separatorStyle = UITableViewCellSeparatorStyle.None;消费者方面相对简单，见下面的例子:

private func stockCell(tableView: UITableView, indexPath:NSIndexPath) -> UITableViewCell {
  var cell : SNStockCell? = tableView.dequeueReusableCellWithIdentifier(stockCellReuseIdentifier) as? SNStockCell
  if (cell == nil) {
    cell = SNStockCell(reuseIdentifier:stockCellReuseIdentifier, primaryTextColor:primaryTextColor, secondaryTextColor:secondaryTextColor)
  }
  cell!.configureWithStock(stockAtIndexPath(indexPath))
  cell!.showsCustomLineSeparator = true
  cell!.customLineSeparatorColor = tintColor
  return cell!
}