获取UILabel上最后一个字符串的位置。获取文字长度和高度，自动换行

//行的高度。
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
   NewNotificationCell *cell = (NewNotificationCell *)[self tableView:tableView cellForRowAtIndexPath:indexPath];
    cell.myLabel.text = [self.dataArray objectAtIndex:indexPath.row];
    labelSize = [cell.myLabel.text sizeWithFont:[UIFont fontWithName:@"Arial" size:15] constrainedToSize:CGSizeMake(cell.myLabel.frame.size.width, 1000) lineBreakMode:UILineBreakModeWordWrap];
    cell.myLabel.lineBreakMode = UILineBreakModeWordWrap;
    cell.myLabel.numberOfLines = 0;
    [cell.myLabel setFont:[UIFont fontWithName:@"Arial" size:15]];
    cell.myLabel.frame = CGRectMake(0, 0, labelSize.width, labelSize.height);
   

    return labelSize.height+30;
   
}
//显示每行的内容。
- (NewNotificationCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    NewNotificationCell*cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (!cell) {
        cell=[[[NewNotificationCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier]autorelease];
        cell = [[[NSBundle mainBundle]loadNibNamed:@"NewNotificationCell" owner:self options:nil]objectAtIndex:0];
       
    }
    //自动换行。
    cell.myLabel.text = [self.dataArray objectAtIndex:indexPath.row];
    labelSize = [cell.myLabel.text sizeWithFont:[UIFont fontWithName:@"Arial" size:15] constrainedToSize:CGSizeMake(cell.myLabel.frame.size.width, 1000) lineBreakMode:UILineBreakModeWordWrap];
    cell.myLabel.lineBreakMode = UILineBreakModeWordWrap;
    cell.myLabel.numberOfLines = 0;
    [cell.myLabel setFont:[UIFont fontWithName:@"Arial" size:15]];
    cell.myLabel.frame = CGRectMake(0, 0, labelSize.width, labelSize.height);
   
    //获取文字长度和高度。
    CGSize fontSize =[cell.myLabel.text sizeWithFont:cell.myLabel.font
                                    forWidth:cell.myLabel.frame.size.width
                               lineBreakMode:UILineBreakModeWordWrap];
    NSLog(@"文字长度=%f",fontSize.width);
   
    //获取UILabel上最后一个字符串的位置。
    CGPoint lastPoint;
    CGSize sz = [cell.myLabel.text sizeWithFont:cell.myLabel.font constrainedToSize:CGSizeMake(MAXFLOAT, 40)];
   
    CGSize linesSz = [cell.myLabel.text sizeWithFont:cell.myLabel.font constrainedToSize:CGSizeMake(cell.myLabel.frame.size.width, MAXFLOAT) lineBreakMode:UILineBreakModeWordWrap];
    if(sz.width <= linesSz.width) //判断是否折行 
    { 
        lastPoint = CGPointMake(cell.myLabel.frame.origin.x + sz.width, cell.myLabel.frame.origin.y);   
    }
    else
    {
        lastPoint = CGPointMake(cell.myLabel.frame.origin.x + (int)sz.width % (int)linesSz.width,linesSz.height - sz.height);
    }
    NSLog(@"====%f",lastPoint.x);
   
   
    [cell.myButton setTitle:@"查看" forState:UIControlStateNormal];
    [cell.myButton setBackgroundImage:[UIImage imageNamed:@"button.png"] forState:UIControlStateNormal];
    if ([cell.myButton.titleLabel.text isEqualToString:@"查看"]) {
        cell.myButton.frame = CGRectMake(lastPoint.x+5, labelSize.height-19, 30, 20);
    }
    [cell.timeButton setTitle:@"今天" forState:UIControlStateNormal];
    cell.timeButton.frame = CGRectMake(260, labelSize.height+8, 50, 20);
    return cell;
}