在 pdf 文档的两页或多页上绘制一长串文本的推荐方法是什么？

当您绘制的文本字符串对于单个页面来说太长时，文本会在文档末尾被剪裁掉。我最初的想法是计算当前页面上可以绘制多少字符串，然后将字符串拆分为两个子字符串:(1) 可以在当前页面上绘制的部分和 (2) 被剪裁的部分。下一步将是重复此过程，直到绘制出整个字符串。

问题仍然是如何计算当前页面上可以绘制多少字符串。我是不是忽略了什么，或者这是一个相当乏味且容易出错的过程？

最佳答案

很久以前我做了这个函数它可能会帮助你，传递间距和字体，它会返回你有限宽度和所需大小的拆分字符串。

- (NSMutableArray *)getSplittedString:(NSString *)largeStr:(UIFont *)font:(NSInteger)horizontalSpace:(float)width {
    NSArray *strWords = [largeStr componentsSeparatedByCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
    //finding space width

    NSInteger currIndex = 0;
    NSString *tmpStr = @"";
    NSString *compareStr = @"";
    NSInteger currWidth;

    NSMutableArray *strArray = [[NSMutableArray alloc] init];
    NSMutableArray *strFrames = [[NSMutableArray alloc] init];

    while(TRUE) {
        while(TRUE) {
            compareStr = tmpStr;
            compareStr = [compareStr stringByAppendingString:[strWords objectAtIndex:currIndex]];
            currWidth = [compareStr sizeWithFont:font].width;
            if(currWidth < width) {
                currIndex = currIndex + 1;
                if(currIndex == [strWords count]) {
                    [strArray addObject:compareStr];
                    [strFrames addObject:[NSValue valueWithCGRect:[self findCenterAdjustedLocation:compareStr :width :font :horizontalSpace]]];
                    break;
                }
                tmpStr = [NSString stringWithFormat:@"%@ ",compareStr];

            } else if (currWidth == width) {
                [strArray addObject:compareStr];
                [strFrames addObject:[NSValue valueWithCGRect:[self findCenterAdjustedLocation:compareStr :width :font :horizontalSpace]]];
                tmpStr = @"";
                if(currIndex == [strWords count]) {
                    break;
                }
            } else {
                if([compareStr rangeOfString:@" "].location == NSNotFound) {
                    while(TRUE) {
                        NSInteger loc = [self findAdjustedLocation:compareStr :width :font];
                        if(loc == 0) {
                            tmpStr = [compareStr substringFromIndex:loc];
                            if(currIndex == [strWords count]) {
                                [strArray addObject:tmpStr];
                                [strFrames addObject:[NSValue valueWithCGRect:[self findCenterAdjustedLocation:tmpStr :width :font :horizontalSpace]]];
                                break;
                            }
                            tmpStr = [NSString stringWithFormat:@"%@ ",tmpStr];
                            break;
                        } else {
                            tmpStr = [compareStr substringWithRange:NSMakeRange(0, loc)];
                            [strArray addObject:tmpStr];
                            [strFrames addObject:[NSValue valueWithCGRect:[self findCenterAdjustedLocation:tmpStr :width :font :horizontalSpace]]];
                            tmpStr = [NSString stringWithFormat:@"%@ ",[compareStr substringFromIndex:loc]];
                            compareStr = tmpStr;
                            if ([tmpStr sizeWithFont:font].width < width) {
                                [strArray addObject:tmpStr];
                                [strFrames addObject:[NSValue valueWithCGRect:[self findCenterAdjustedLocation:tmpStr :width :font :horizontalSpace]]];
                                currIndex = currIndex + 1;
                                break;
                            }
                        }
                    }
                } else {
                    [strArray addObject:tmpStr];
                    [strFrames addObject:[NSValue valueWithCGRect:[self findCenterAdjustedLocation:tmpStr :width :font :horizontalSpace]]];
                    tmpStr = @"";
                }
                break;
            }
        }
        if(currIndex == [strWords count]) {
            return [[NSMutableArray alloc] initWithObjects:strArray, strFrames, nil];
            break;
        }
    }
}

关于iOS:在 PDF 文档的多个页面上绘制文本，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/12154334/