This is not as short as the other examples, but takes an entirely different approach to solving this problem. Note, the caret will still begin flush to the left edge but the text will be properly indented when typed/displayed. This works without subclassing if your looking for just a left margin and you are already using UITextFieldDelegate for your text fields. You need to set both the default text attributes and the typing attributes. You set the default text attributes when you create the text field. The typing attributes you need to set in the delegate. If you are also using a placeholder you will want to set that to the same margin as well. Putting it altogether you get something like this.

首先在UITextField类上创建一个类别。

//  UITextField+TextAttributes.h

#import <UIKit/UIKit.h>

@interface UITextField (TextAttributes)

- (void)setIndent:(CGFloat)indent;

@end


//  UITextField+TextAttributes.m
#import "UITextField+TextAttributes.h"

@implementation UITextField (TextAttributes)

- (void)setTextAttributes:(NSDictionary*)textAttributes indent:(CGFloat)indent
{
    if (!textAttributes) return;

    NSMutableParagraphStyle *paragraphStyle = [textAttributes objectForKey:NSParagraphStyleAttributeName];
    paragraphStyle.firstLineHeadIndent = indent;
    paragraphStyle.headIndent = indent;
}

- (void)setIndent:(CGFloat)indent
{
   [self setTextAttributes:self.defaultTextAttributes indent:indent];
   [self setTextAttributes:self.typingAttributes indent:indent];
}

@end

然后，如果您使用放置占位符，请确保使用带有属性的占位符设置相同的缩进。创建一个具有正确属性的默认属性字典，如下所示:

NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
paragraphStyle.firstLineHeadIndent = 7;
paragraphStyle.headIndent = 7;
NSDictionary *placeholderAttributes = [NSDictionary dictionaryWithObjectsAndKeys: paragraphStyle, NSParagraphStyleAttributeName, nil];

然后，导入上述类别，每当你创建一个文本字段设置默认缩进，委托和使用默认占位符属性上面定义。例如:

UITextField *textField = [[UITextField alloc] init];
textField.indent = 7;
textField.delegate = self;
textField.attributedPlaceholder = [[NSAttributedString alloc] initWithString:@"Placeholder Text" attributes:placeholderAttributes];

最后，在委托中，实现textFieldDidBeginEditing方法，就像这样:

- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    textField.indent = 7;
}

你可以通过设置leftView来设置UITextField的文本插入。

是这样的:

UITextField *yourTextField = [[UITextField alloc] init];
UIView *leftView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 5, 5)];
leftView.backgroundColor = [UIColor clearColor];
yourTextField.leftViewMode = UITextFieldViewModeAlways;
yourTextField.leftView = leftView;

下面是一个全面的Swift答案，包括一个leftView(自定义图标)和一个自定义清除按钮，两者都设置在界面生成器中，具有可定制的insets。

import UIKit

@IBDesignable
class InsetTextField: UITextField {
@IBInspectable var leftInset:CGFloat = 0
@IBInspectable var rightInset:CGFloat = 0
@IBInspectable var icon:UIImage? { didSet {
    let imageView = UIImageView(frame: CGRect(x: 0, y: 0, width: 16, height: 16))
    imageView.image = icon
    self.leftView = imageView
    self.leftViewMode = .Always
} }

@IBInspectable var clearButton:UIImage? { didSet {
    let button = UIButton(type: .Custom)
    button.setImage(clearButton, forState: .Normal)
    button.addTarget(self, action: "clear", forControlEvents: UIControlEvents.TouchUpInside)
    button.frame = CGRect(x: 0, y: 0, width: 18, height: 18)
    self.rightView = button
    self.rightViewMode = .WhileEditing
} }

func clear() {
    self.text = ""
}

override func leftViewRectForBounds(bounds: CGRect) -> CGRect {
    var height:CGFloat = 0
    var width:CGFloat = 0
    if let leftView = self.leftView {
        height = leftView.bounds.height
        width = leftView.bounds.width
    }

    return CGRect(x: leftInset, y: bounds.height/2 - height/2, width: width, height: height)
}

override func rightViewRectForBounds(bounds: CGRect) -> CGRect {
    var height:CGFloat = 0
    var width:CGFloat = 0
    if let rightView = self.rightView {
        height = rightView.bounds.height
        width = rightView.bounds.width
    }

    return CGRect(x: bounds.width - width - rightInset, y: bounds.height/2 - height/2, width: width, height: height)
}

}

斯威夫特

 class TextField: UITextField {

    let inset: CGFloat = 8

    // placeholder position
    override func textRect(forBounds bounds: CGRect) -> CGRect {
        return bounds.insetBy(dx: inset, dy: inset)
    }

    // text position
    override func editingRect(forBounds bounds: CGRect) -> CGRect {
        return bounds.insetBy(dx: inset, dy: inset)
    }
}

Swift 4.2版本:

import UIKit

class InsetTextField: UITextField {

  let inset: CGFloat = 10

  override func textRect(forBounds bounds: CGRect) -> CGRect {
    return bounds.insetBy(dx: inset, dy: inset)
  }


  override func editingRect(forBounds bounds: CGRect) -> CGRect {
    return bounds.insetBy(dx: inset, dy: inset)
  }

  override func placeholderRect(forBounds bounds: CGRect) -> CGRect {
    return bounds.insetBy(dx: inset, dy: inset)
  }

}

如果你只需要左边空白，你可以试试这个:

UItextField *textField = [[UITextField alloc] initWithFrame:...];
UIView *leftView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 10, textField.frame.size.height)];
leftView.backgroundColor = textField.backgroundColor;
textField.leftView = leftView;
textField.leftViewMode = UITextFieldViewModeAlways;

这对我很管用。我希望这能有所帮助。