我创建了这个类别实现，并将其添加到.m文件的顶部。

@implementation UITextField (custom)
    - (CGRect)textRectForBounds:(CGRect)bounds {
        return CGRectMake(bounds.origin.x + 10, bounds.origin.y + 8,
                          bounds.size.width - 20, bounds.size.height - 16);
    }
    - (CGRect)editingRectForBounds:(CGRect)bounds {
        return [self textRectForBounds:bounds];
    }
@end

根据彼得·布拉斯亚克提供的链接。这似乎比创建一个全新的子类更简单，也比添加额外的UIView更简单。不过，似乎缺少了一些东西，无法控制文本字段内的填充。

Swift 4解决方案:

class CustomTextField: UITextField {
    struct Constants {
        static let sidePadding: CGFloat = 10
        static let topPadding: CGFloat = 8
    }

    override func textRect(forBounds bounds: CGRect) -> CGRect {
        return CGRect(
            x: bounds.origin.x + Constants.sidePadding,
            y: bounds.origin.y + Constants.topPadding,
            width: bounds.size.width - Constants.sidePadding * 2,
            height: bounds.size.height - Constants.topPadding * 2
        )
    }

    override func editingRect(forBounds bounds: CGRect) -> CGRect {
        return self.textRect(forBounds: bounds)
    }
}

Swift 2.0版本:

let paddingView: UIView = UIView(frame: CGRectMake(0, 0, 5, 20))
textField.leftView = paddingView
textField.leftViewMode = UITextFieldViewMode.Always;

你可以使用分类。设置左填充和右填充

UITextField+Padding.h

@interface UITextField (Padding)
@property (nonatomic, assign) CGFloat paddingValue;
@property (nonatomic, assign) CGFloat leftPadding;
@property (nonatomic, assign) CGFloat rightPadding;

//overwrite
-(CGRect)textRectForBounds:(CGRect)bounds;
-(CGRect)editingRectForBounds:(CGRect)bounds;
@end

UITextField+Padding.m

#import "UITextField+Padding.h"
#import <objc/runtime.h>

static char TAG_LeftPaddingKey;
static char TAG_RightPaddingKey;
static char TAG_Left_RightPaddingKey;

@implementation UITextField (Padding)

#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wobjc-protocol-method-implementation"
-(CGRect)textRectForBounds:(CGRect)bounds {

CGFloat offset_Left=0;
CGFloat offset_Right=0;
if (self.paddingValue>0) {
    offset_Left=self.paddingValue;
    offset_Right=offset_Left;
}else{
    if (self.leftPadding>0){
        offset_Left=self.leftPadding;
    }
    if (self.rightPadding>0){
        offset_Right=self.rightPadding;
    }
}

if (offset_Left>0||offset_Right>0) {
    return CGRectMake(bounds.origin.x+ offset_Left ,bounds.origin.y ,
                      bounds.size.width- (offset_Left+offset_Right), bounds.size.height-2 );
 }else{
    return bounds;
 }
}



-(CGRect)editingRectForBounds:(CGRect)bounds {
    return [self textRectForBounds:bounds];
}
#pragma clang diagnostic pop


#pragma maek -setter&&getter
- (CGFloat)paddingValue
{
    return [objc_getAssociatedObject(self,&TAG_Left_RightPaddingKey) floatValue];
}
-(void)setPaddingValue:(CGFloat)paddingValue
{
    objc_setAssociatedObject(self, &TAG_Left_RightPaddingKey, @(paddingValue), OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

-(CGFloat)leftPadding
{
    return [objc_getAssociatedObject(self,&TAG_LeftPaddingKey) floatValue];
}

-(void)setLeftPadding:(CGFloat)leftPadding
{
    objc_setAssociatedObject(self, &TAG_LeftPaddingKey, @(leftPadding), OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

-(CGFloat)rightPadding
{
    return [objc_getAssociatedObject(self,&TAG_RightPaddingKey) floatValue];
}

-(void)setRightPadding:(CGFloat)rightPadding
{
    objc_setAssociatedObject(self, &TAG_RightPaddingKey, @(rightPadding), OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

@end

你可以像这样设置填充 self.phoneNumTF.paddingValue f = 10.; 或 self.phoneNumTF.leftPadding f = 10.;

就像这样子类UITextField (Swift版本):

import UIKit

class CustomTextField: UITextField {

    override func textRectForBounds(bounds: CGRect) -> CGRect {
       return CGRectInset(bounds, 25.0, 0)
    }

    override func editingRectForBounds(bounds: CGRect) -> CGRect {
       return self.textRectForBounds(bounds)
    }

}

这增加了25.0点的水平填充两边。

创建一个文本域Custom

PaddingTextField.swift

import UIKit
class PaddingTextField: UITextField {

@IBInspectable var paddingLeft: CGFloat = 0
@IBInspectable var paddingRight: CGFloat = 0

override func textRectForBounds(bounds: CGRect) -> CGRect {
    return CGRectMake(bounds.origin.x + paddingLeft, bounds.origin.y,
        bounds.size.width - paddingLeft - paddingRight, bounds.size.height);
}

override func editingRectForBounds(bounds: CGRect) -> CGRect {
    return textRectForBounds(bounds)
}}

设置你的文本字段类是PaddingTextField和自定义你的填充，因为你想要 享受它

我是基于Nate的解决方案，但后来我发现，这导致问题，当你使用leftView/rightView属性，所以它更好地调优超级的实现，因为它将左/右视图的考虑。

- (CGRect)textRectForBounds:(CGRect)bounds {
    CGRect ret = [super textRectForBounds:bounds];
    ret.origin.x = ret.origin.x + 5;
    ret.size.width = ret.size.width - 10;
    return ret;
}

- (CGRect)editingRectForBounds:(CGRect)bounds {
    return [self textRectForBounds:bounds];
}