最好使用自动尺寸(Swift):

  tableView.estimatedRowHeight = 68.0
  tableView.rowHeight = UITableViewAutomaticDimension

注: 1. UITableViewCell原型应该正确设计(对于实例不要忘记设置UILabel。numberolines = 0 etc) 2. 删除hightforrowatindexpath方法

视频: https://youtu.be/Sz3XfCsSb6k

你仍然可以使用sizeWithFont。但是，在iOS >= 7.0中，如果字符串包含开头和结尾空格或结束行\n，则会导致崩溃。

在使用文本之前修剪文本

label.text = [label.text stringByTrimmingCharactersInSet:
             [NSCharacterSet whitespaceAndNewlineCharacterSet]];

这也适用于sizeWithAttributes和[label sizeToFit]。

此外，当你有nsstringdrawingtextstorage消息发送到deallocated实例在ios7.0设备它处理这个。

基于@bitsand，这是一个新方法，我刚刚添加到我的NSString+Extras类别:

- (CGRect) boundingRectWithFont:(UIFont *) font constrainedToSize:(CGSize) constraintSize lineBreakMode:(NSLineBreakMode) lineBreakMode;
{
    // set paragraph style
    NSMutableParagraphStyle *style = [[NSParagraphStyle defaultParagraphStyle] mutableCopy];
    [style setLineBreakMode:lineBreakMode];

    // make dictionary of attributes with paragraph style
    NSDictionary *sizeAttributes = @{NSFontAttributeName:font, NSParagraphStyleAttributeName: style};

    CGRect frame = [self boundingRectWithSize:constraintSize options:NSStringDrawingUsesLineFragmentOrigin attributes:sizeAttributes context:nil];

    /*
    // OLD
    CGSize stringSize = [self sizeWithFont:font
                              constrainedToSize:constraintSize
                                  lineBreakMode:lineBreakMode];
    // OLD
    */

    return frame;
}

我只是使用结果帧的大小。

CGSize maximumLabelSize = CGSizeMake(label.frame.size.width, FLT_MAX);
CGSize expectedLabelSize = [label sizeThatFits:maximumLabelSize];
float heightUse = expectedLabelSize.height;

替代解决方案,

CGSize expectedLabelSize;
if ([subTitle respondsToSelector:@selector(sizeWithAttributes:)])
{
    expectedLabelSize = [subTitle sizeWithAttributes:@{NSFontAttributeName:subTitleLabel.font}];
}else{
    expectedLabelSize = [subTitle sizeWithFont:subTitleLabel.font constrainedToSize:subTitleLabel.frame.size lineBreakMode:NSLineBreakByWordWrapping];
}

如果有人需要的话，这里有一个单一的对等物:

/// <summary>
/// Measures the height of the string for the given width.
/// </summary>
/// <param name="text">The text.</param>
/// <param name="font">The font.</param>
/// <param name="width">The width.</param>
/// <param name="padding">The padding.</param>
/// <returns></returns>
public static float MeasureStringHeightForWidth(this string text, UIFont font, float width, float padding = 20)
{
    NSAttributedString attributedString = new NSAttributedString(text, new UIStringAttributes() { Font = font });
    RectangleF rect = attributedString.GetBoundingRect(new SizeF(width, float.MaxValue), NSStringDrawingOptions.UsesLineFragmentOrigin, null);
    return rect.Height + padding;
}

可以这样使用:

public override float GetHeightForRow(UITableView tableView, NSIndexPath indexPath)
{
    //Elements is a string array
    return Elements[indexPath.Row].MeasureStringHeightForWidth(UIFont.SystemFontOfSize(UIFont.LabelFontSize), tableView.Frame.Size.Width - 15 - 30 - 15);
}