对于Swift 2:

将以下行添加到viewDidLoad():

tableView.separatorColor = UIColor.clearColor()

对于iOS7或更高版本，更简洁的方法是使用INFINITY而不是硬编码的值。当屏幕旋转时，您不必担心更新单元格。

if (indexPath.row == <row number>) {
    cell.separatorInset = UIEdgeInsetsMake(0, INFINITY, 0, 0);
}

你必须采取自定义单元格，并添加标签和设置约束，如标签应覆盖整个单元格区域。 并在构造函数中编写下面的行。

- (void)awakeFromNib {
    // Initialization code
    self.separatorInset = UIEdgeInsetsMake(0, 10000, 0, 0);
    //self.layoutMargins = UIEdgeInsetsZero;
    [self setBackgroundColor:[UIColor clearColor]];
    [self setSelectionStyle:UITableViewCellSelectionStyleNone];
}

也设置UITableView布局边距如下

tblSignup.layoutMargins = UIEdgeInsetsZero;

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    [self.tableView setSeparatorStyle:UITableViewCellSeparatorStyleNone];
}

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)
    }
}

使用这个子类，set separatorInset在iOS 9.2.1中不起作用，内容会被压缩。

@interface NSPZeroMarginCell : UITableViewCell

@property (nonatomic, assign) BOOL separatorHidden;

@end

@implementation NSPZeroMarginCell

- (void) layoutSubviews {
    [super layoutSubviews];

    for (UIView *view in  self.subviews) {
        if (![view isKindOfClass:[UIControl class]]) {
            if (CGRectGetHeight(view.frame) < 3) {
                view.hidden = self.separatorHidden;
            }
        }
    }
}

@end

https://gist.github.com/liruqi/9a5add4669e8d9cd3ee9