在Swift 3中

import UIKit

let TEXTFIELD_BLUE  = UIColor.blue
let TEXTFIELD_GRAY  = UIColor.gray

class DBTextField: UITextField {
    /// Tetxfield Placeholder Color
    @IBInspectable var palceHolderColor: UIColor = TEXTFIELD_GRAY
    func setupTextField () {
        self.attributedPlaceholder = NSAttributedString(string:self.placeholder != nil ? self.placeholder! : "",
                                                            attributes:[NSForegroundColorAttributeName: palceHolderColor])
    }
}

class DBLocalizedTextField : UITextField {
    override func awakeFromNib() {
        super.awakeFromNib()
        self.placeholder = self.placeholder
    }
}

iOS 6及后续版本在UITextField上提供attributedPlaceholder。 iOS 3.2及更高版本提供了setAttributes:range: on NSMutableAttributedString。

您可以执行以下操作:

NSMutableAttributedString *ms = [[NSMutableAttributedString alloc] initWithString:self.yourInput.placeholder];
UIFont *placeholderFont = self.yourInput.font;
NSRange fullRange = NSMakeRange(0, ms.length);
NSDictionary *newProps = @{NSForegroundColorAttributeName:[UIColor yourColor], NSFontAttributeName:placeholderFont};
[ms setAttributes:newProps range:fullRange];
self.yourInput.attributedPlaceholder = ms;

我需要保持占位符的对齐，这样亚当的答案对我来说就不够了。

为了解决这个问题，我使用了一个小的变化，我希望也能帮助到你们:

- (void) drawPlaceholderInRect:(CGRect)rect {
    //search field placeholder color
    UIColor* color = [UIColor whiteColor];

    [color setFill];
    [self.placeholder drawInRect:rect withFont:self.font lineBreakMode:UILineBreakModeTailTruncation alignment:self.textAlignment];
}

此解决方案适用于Swift 4.1

    textName.attributedPlaceholder = NSAttributedString(string: textName.placeholder!, attributes: [NSAttributedStringKey.foregroundColor : UIColor.red])

在Swift 3中

import UIKit

let TEXTFIELD_BLUE  = UIColor.blue
let TEXTFIELD_GRAY  = UIColor.gray

class DBTextField: UITextField {
    /// Tetxfield Placeholder Color
    @IBInspectable var palceHolderColor: UIColor = TEXTFIELD_GRAY
    func setupTextField () {
        self.attributedPlaceholder = NSAttributedString(string:self.placeholder != nil ? self.placeholder! : "",
                                                            attributes:[NSForegroundColorAttributeName: palceHolderColor])
    }
}

class DBLocalizedTextField : UITextField {
    override func awakeFromNib() {
        super.awakeFromNib()
        self.placeholder = self.placeholder
    }
}

适用于iOS 6.0 +

[textfield setValue:your_color forKeyPath:@"_placeholderLabel.textColor"];

希望能有所帮助。

注意:苹果可能会拒绝(0.01%的机会)你的应用程序，因为我们正在访问私有API。这两年以来，我一直在我的所有项目中使用这个功能，但苹果并没有要求我这么做。