ios開發之--實現TextView提示文字並且輸入字數限制

標籤：desc   idc   substring   length   nal   long   ios開發   set   oid   

實現字數控制和限制，並展示當前輸入的字串長度，以及按鈕的點擊狀態，代碼如下：

1，設定代理

@interface FKViewController ()<UITextViewDelegate>@property (weak, nonatomic) IBOutlet UITextView *FKTextView;@property (weak, nonatomic) IBOutlet UILabel *descLab;@property (weak, nonatomic) IBOutlet UIButton *sendBtn;@property (weak, nonatomic) IBOutlet UILabel *stringlenghtLab;

2，設定初始狀態

- (void)viewDidLoad {    [super viewDidLoad];    // Do any additional setup after loading the view from its nib.        self.view.backgroundColor = BackgroundColor;    self.navigationController.navigationBarHidden = YES;    CustomNavigationBar *nav = [[CustomNavigationBar alloc]initWithFrame:CGRectMake(0, 0, KscreenW, NavHeight) withTitle:@"意見反饋" withLeftBtnHidden:NO withRightBtn:YES];    nav.delegate = self;    [self.view addSubview:nav];        self.FKTextView.delegate = self;    self.descLab.userInteractionEnabled = NO;    self.sendBtn.userInteractionEnabled = NO;    self.sendBtn.backgroundColor = [UIColor lightGrayColor];}

3，代理方法的實現

-(void)textViewDidChange:(UITextView *)textView{    self.descLab.hidden = YES;    self.sendBtn.userInteractionEnabled = YES;    self.sendBtn.backgroundColor = MainColor;    //即時顯示字數    self.stringlenghtLab.text = [NSString stringWithFormat:@"%ld/100",(long)textView.text.length];        //字數限制    if (textView.text.length >= 100) {        textView.text = [textView.text substringToIndex:100];    }        //取消安潤點擊許可權，並顯示文字    if (textView.text.length == 0) {        self.descLab.hidden = NO;        self.sendBtn.userInteractionEnabled = NO;        self.sendBtn.backgroundColor = [UIColor lightGrayColor];    }}

字串長度為0時，按鈕返回初始狀態，有輸入字元時，顯示為可點擊狀態，很簡單，僅做記錄用！

ios開發之--實現TextView提示文字並且輸入字數限制