ios 如何为 UILabel 添加换行符？

How to add line break for UILabel?

提问by Thang Pham

Let see that I have a string look like this:

让我们看看我有一个像这样的字符串：

NSString *longStr = @"AAAAA\nBBBBB\nCCCCC";  

How do I make it so that the UILabel display the message like this

如何让 UILabel 显示这样的消息

AAAAA
BBBBB
CCCCC

AAAAA
BBBBB
CCCCC

I don't think \nis recognized by UILabel, so is there anything that I can put inside NSString so that UILabel knows that it has to create a line break there?

我认为\nUILabel无法识别，所以我可以在 NSString 中放入任何内容，以便 UILabel 知道它必须在那里创建换行符？

回答by Gerry Shaw

Use \nas you are using in your string.

使用\n如您使用的是您的字符串。

Set numberOfLines to 0 to allow for any number of lines.

将 numberOfLines 设置为 0 以允许任意数量的行。

label.numberOfLines = 0;

label.numberOfLines = 0;

Update the label frame to match the size of the text using sizeWithFont:. If you don't do this your text will be vertically centered or cut off.

使用 更新标签框架以匹配文本的大小sizeWithFont:。如果您不这样做，您的文本将垂直居中或被切断。

UILabel *label; // set frame to largest size you want
...
CGSize labelSize = [label.text sizeWithFont:label.font
                          constrainedToSize:label.frame.size
                              lineBreakMode:label.lineBreakMode];
label.frame = CGRectMake(
    label.frame.origin.x, label.frame.origin.y, 
    label.frame.size.width, labelSize.height);

Update : Replacement for deprecated

更新：替换已弃用

sizeWithFont:constrainedToSize:lineBreakMode:sizeWithFont:constrainedToSize:lineBreakMode:

Reference, Replacement for deprecated sizeWithFont: in iOS 7?

参考，替换已弃用的 sizeWithFont：在 iOS 7 中？

CGSize labelSize = [label.text sizeWithAttributes:@{NSFontAttributeName:label.font}];

label.frame = CGRectMake(
    label.frame.origin.x, label.frame.origin.y, 
    label.frame.size.width, labelSize.height);

回答by Marco

Use option-return when typing in the little box in Interface Builder to insert a line feed (\n). In Interface Builder's Label attributes, set # Lines = 0.

在 Interface Builder 的小框中键入以插入换行符 (\n) 时使用 option-return。在 Interface Builder 的 Label 属性中，设置 # Lines = 0。

Select the label and then change Lines property to 0 like in the above image, and then use \n in your string for line break.

选择标签，然后像上图一样将 Lines 属性更改为 0，然后在字符串中使用 \n 进行换行。

回答by Al-Noor Ladhani

If you read a string from an XML file, the line break \nin this string will not work in UILabeltext. The \nis not parsed to a line break.

如果您从 XML 文件中读取字符串，则\n该字符串中的换行符在UILabel文本中不起作用。该\n不会被解析到一个换行符。

Here is a little trick to solve this issue:

这里有一个小技巧可以解决这个问题：

// correct next line \n in string from XML file
NSString *myNewLineStr = @"\n";
myLabelText = [myLabelText stringByReplacingOccurrencesOfString:@"\n" withString:myNewLineStr];

myLabel.text = myLabelText;

So you have to replace the unparsed \npart in your string by a parsed \nin a hardcoded NSString.

因此，您必须将\n字符串中未解析的部分替换\n为硬编码NSString.

Here are my other label settings:

这是我的其他标签设置：

myLabel.numberOfLines = 0;
myLabel.backgroundColor = [UIColor lightGrayColor];
myLabel.textColor = [UIColor redColor]; 
myLabel.font = [UIFont fontWithName:@"Helvetica Neue" size:14.0];   
myLabel.textAlignment = UITextAlignmentCenter;

Most important is to set numberOfLinesto 0(= unlimited number of lines in label).

最重要的是设置numberOfLines为0（= 标签中的行数不受限制）。

No idea why Apple has chosen to not parse \nin strings read from XML?

不知道为什么 Apple 选择不解析\n从 XML 读取的字符串？

Hope this helps.

希望这可以帮助。

回答by kuokuo321

In the interface builder, you can use Ctrl+ Enterto insert /nto the position you want. This way could implement the following situation

在界面构建器中，您可以使用Ctrl+Enter插入/n到您想要的位置。这种方式可以实现以下情况

aaa
aaaaaaa

AAA
AAAAAAA

回答by Dan

You have to set the numberOfLinesproperty on the UILabel. The default is 1, if you set it to 0it will remove all limits.

您必须numberOfLines在UILabel. 默认值为1，如果将其设置为0将删除所有限制。

回答by AndyOng

Important to note it's \n(backslash) rather than /n.

重要的是要注意它是\n（反斜杠）而不是/n.

回答by CodeOverRide

In Swift 2.2, > iOS 8

在 Swift 2.2 中，> iOS 8

I've set Lines = 0 on Storyboard, under Attribute Inspector and linked a referencing outlet to the label. Then use in controller like this:

我在 Storyboard 上的 Attribute Inspector 下设置了 Lines = 0，并将引用出口链接到标签。然后像这样在控制器中使用：

 @IBOutlet weak var listLabel: UILabel!

 override func viewDidLoad() {
      ...
      listLabel.text = "Line 1\nLine 2\nLine 3\nLine 4\nLine 5\nLine 6\nLine 7\nLine 8"
 }

回答by Sandip Patel - SM

Just do it like this

就这样做

NSString * strCheck = @"A\nB";

strCheck = [strCheck stringByReplacingOccurrencesOfString:@"\n" withString:@"\n"];  //This is to prevent for fetching string from plist or data structure

label.numberOfLines = 0;

label.lineBreakMode = NSLineBreakByWordWrapping;

label.text = strCheck;

回答by Pankaj Chauhan

// DO not forget to set numberOfLines to zero

// 不要忘记将 numberOfLines 设置为零

UILabel* locationTitle = [[UILabel alloc] initWithFrame:CGRectMake(5, 30, 230, 40)];
locationTitle.font = [UIFont systemFontOfSize:13.0];
locationTitle.numberOfLines = 0;
locationTitle.text = [NSString stringWithFormat:@"Eaton industries pvt. Ltd \nUK Apr 12"];
[cell addSubview:locationTitle];

回答by Roi

On Xcode 6, you can just use \n even inside a string when using word wrap. It will work. So for example:

在 Xcode 6 上，使用自动换行时，您甚至可以在字符串内使用 \n。它会起作用。例如：

UILabel *label = [[UILabel alloc]initWithFrame:CGRectMake(0, 100, screenRect.size.width, 50)];
label.textAlignment = NSTextAlignmentCenter;
label.text = @"This will be on the first line\nfollowed by a line under it.";
label.lineBreakMode = UILineBreakModeWordWrap;
label.numberOfLines = 0;