如何在Objective

在图像内绘制文本并返回结果图像：

+(UIImage*) drawText:(NSString*) text   inImage:(UIImage*)  image   atPoint:(CGPoint)   point {    UIFont *font = [UIFont boldSystemFontOfSize:12];    UIGraphicsBeginImageContext(image.size);    [image drawInRect:CGRectMake(0,0,image.size.width,image.size.height)];    CGRect rect = CGRectMake(point.x, point.y, image.size.width, image.size.height);    [[UIColor whiteColor] set];    [text drawInRect:CGRectIntegral(rect) withFont:font];     UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();    UIGraphicsEndImageContext();    return newImage;}

用法：

// note: replace "ImageUtils" with the class where you pasted the method aboveUIImage *img = [ImageUtils drawText:@"Some text"      inImage:img       atPoint:CGPointMake(0, 0)];

将图像内文本的原点从0,0更改为所需的任意点。

要在文本后面绘制纯色矩形，请在该行之前添加以下内容[[UIColor whiteColor] set];：

[[UIColor brownColor] set];CGContextFillRect(UIGraphicsGetCurrentContext(),        CGRectMake(0, (image.size.height-[text sizeWithFont:font].height),  image.size.width, image.size.height));

我正在使用文本大小来计算纯色矩形的原点，但是您可以将其替换为任何数字。