使用Swift 2.2

创建UITableViewCell扩展

import UIKit

extension UITableViewCell {
    func removeMargins() {

        if self.respondsToSelector(Selector("setSeparatorInset:")) {
            self.separatorInset = UIEdgeInsetsZero
        }

        if self.respondsToSelector(Selector("setPreservesSuperviewLayoutMargins:")) {
            self.preservesSuperviewLayoutMargins = false
        }

        if self.respondsToSelector(Selector("setLayoutMargins:")) {
            self.layoutMargins = UIEdgeInsetsZero
        }
    }
} 

现在可以在cellForRowAtIndex中使用

-(void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath
{
            cell.removeMargins()//To remove seprator inset 
}

使用下面的代码片段避免不必要的填充问题UITableView在IOS 8和7。

-(void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath{

    if ([tableView respondsToSelector:@selector(setSeparatorInset:)])
    {
        [tableView setSeparatorInset:UIEdgeInsetsZero];
    }

    if ([tableView respondsToSelector:@selector(setLayoutMargins:)])
    {
        [tableView setLayoutMargins:UIEdgeInsetsZero];
    }

    if ([cell respondsToSelector:@selector(setLayoutMargins:)])
    {
        [cell setLayoutMargins:UIEdgeInsetsZero];
    }
}

下面是来自@cdstamper的回答，一个更好的地方是UITableViewCell的layoutSubviews，在你的单元格文件中(我设置了1%的间距，你可以设置为零)，所以只需要在这里设置代码来处理所有情况(旋转和其他):

 -(void)layoutSubviews
    {
        [super layoutSubviews];
        if ([self respondsToSelector:@selector(setSeparatorInset:)]) {
            [self setSeparatorInset:UIEdgeInsetsMake(0,self.bounds.size.width*0.01,0,self.bounds.size.width*0.01)];
        }
        if ([self respondsToSelector:@selector(setLayoutMargins:)]) {
            [self setLayoutMargins:UIEdgeInsetsMake(0,self.bounds.size.width*0.01,0,self.bounds.size.width*0.01)];
        }
    }

Swift 2.0扩展

我只是想分享一个扩展，我做了删除边缘从tableview单元格分隔符。

extension UITableViewCell {
    func removeMargins() {

        if self.respondsToSelector("setSeparatorInset:") {
            self.separatorInset = UIEdgeInsetsZero
        }

        if self.respondsToSelector("setPreservesSuperviewLayoutMargins:") {
            self.preservesSuperviewLayoutMargins = false
        }

        if self.respondsToSelector("setLayoutMargins:") {
            self.layoutMargins = UIEdgeInsetsZero
        }
    }
}

用于上下文中:

    let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as! CustomCell

    cell.removeMargins()
    return cell

大多数答案是显示分隔符插入和布局边距设置在各种方法(即viewDidLayoutSubviews, willDisplayCell等)的单元格和表视图，但我发现，只是把这些cellForRowAtIndexPath工作得很好。似乎是最干净的方法。

// kill insets for iOS 8
if ([[UIDevice currentDevice].systemVersion floatValue] >= 8) {
    cell.preservesSuperviewLayoutMargins = NO;
    [cell setLayoutMargins:UIEdgeInsetsZero];
}
// iOS 7 and later
if ([cell respondsToSelector:@selector(setSeparatorInset:)])
    [cell setSeparatorInset:UIEdgeInsetsZero];

以一种比大多数人投票的答案更紧凑的方式……

- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath {

    if ([cell respondsToSelector:@selector(setSeparatorInset:)] && [cell respondsToSelector:@selector(setPreservesSuperviewLayoutMargins:)] && [cell respondsToSelector:@selector(setLayoutMargins:)]) {
         [cell setSeparatorInset:UIEdgeInsetsZero];
         [cell setPreservesSuperviewLayoutMargins:NO];
         [cell setLayoutMargins:UIEdgeInsetsZero];
    }

}