UILabel文字居左顯示隅很，實(shí)現(xiàn)文字居左顯示代碼如下：
UILabel *label = [[UILabel alloc] init];
label.frame = CGRectMake(50, 100, 200, 50);
label.text = @"label";
label.textAlignment = NSTextAlignmentLeft;
label.backgroundColor = [UIColor orangeColor];
[self.view addSubview:label];
按照UILabel文字居左的寫法叔营，UIButton應(yīng)該這么寫：
button.titleLabel.textAlignment = NSTextAlignmentLeft;
我們發(fā)現(xiàn)UIButton的文字還是居中顯示所宰。竟然沒(méi)有居左顯示仔粥，怎么辦呢？進(jìn)UIButton看看谭羔，還有哪些屬性麦向。很快發(fā)現(xiàn)：
@property(nonatomic) UIControlContentHorizontalAlignment contentHorizontalAlignment; // how to position content hozontally inside control. default is center
typedef NS_ENUM(NSInteger, UIControlContentHorizontalAlignment) {
UIControlContentHorizontalAlignmentCenter = 0,
UIControlContentHorizontalAlignmentLeft = 1,
UIControlContentHorizontalAlignmentRight = 2,
UIControlContentHorizontalAlignmentFill = 3,
};
設(shè)置contentHorizontalAlignment
button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentLeft;
完成＞懊琛十办！ 如果感覺(jué)看著居左顯示很難看，太靠邊呵燕〖啵可以設(shè)置UIButton的titleEdgeInsets屬性：
button.titleEdgeInsets = UIEdgeInsetsMake(0, 10, 0, 0);
這樣button的title就距左邊10個(gè)像素的距離。
同理居右顯示：
button.contentHorizontalAlignment = UIControlContentHorizontalAlignmentRight;
