IOS计算字符串尺寸

.h

#import <Foundation/Foundation.h>

@interface NSString (Extension)
/**
 *  返回字符串所占用的尺寸
 *
 *  @param font    字体
 *  @param maxSize 最大尺寸
 */
- (CGSize)sizeWithFont:(UIFont *)font maxSize:(CGSize)maxSize;
@end

。m

#import "NSString+Extension.h"

@implementation NSString (Extension)
- (CGSize)sizeWithFont:(UIFont *)font maxSize:(CGSize)maxSize
{
    NSDictionary *attrs = @{NSFontAttributeName : font};
    return [self boundingRectWithSize:maxSize options:NSStringDrawingUsesLineFragmentOrigin attributes:attrs context:nil].size;
}
@end