typescript 如何添加验证模式以不允许在输入 Angular2 中只留空间？
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How to add Validation pattern not to allow only space in input Angular2?
提问by Poonam Thote
I used formBuilder in Angular2 and want to add validation pattern for not to allow "only spaces" in input.
我在 Angular2 中使用了 formBuilder 并希望添加验证模式以不允许输入中的“仅空格”。
回答by Rahul Tank
try this, it will return false while sapce key press :
试试这个，它会在按下 sapce 键时返回 false：
@Component({
selector: 'my-app',
template: `
<div>
<input class="form-control" type="number" formControlName="pinCode" placeholder="Pin Code"
(keydown.space)="$event.preventDefault()">
</div>
`,
providers: [myService]
})
visit for more Events :
更多活动请访问：
回答by Pardeep Jain
space Not allowed
空格 不允许
let nospacePattern = [a-zA-Z0-9]
Update
更新
As per requirement in comment section.
根据评论部分的要求。
need pattern not to allow only spaces. (space in between words are allowed).but when user enter spaces in input and try to save it then it should not allow to save
需要模式不能只允许空格。（单词之间的空格是允许的）。但是当用户在输入中输入空格并尝试保存时，它不应该允许保存
Validators.pattern(".*\S.*[a-zA-z0-9 ]");
Update 2
更新 2
Better and Cleaner way to use custom validation pattern like below -
使用如下自定义验证模式的更好更简洁的方法 -
controlName: ['', [Validators.required, this.noWhitespaceValidator]],
....
....
noWhitespaceValidator(control: FormControl) {
const isWhitespace = (control && control.value && control.value.toString() || '').trim().length === 0;
const isValid = !isWhitespace;
return isValid ? null : { 'whitespace': true };
}
回答by sangRam
hey i know i am very late in party but i have also faced same issue on which i have tired following code and it works :
嘿，我知道我参加聚会很晚了，但我也遇到了同样的问题，我厌倦了以下代码并且它有效：
as per my requirement, in form comment box should be has min 30 character and that character should be non-space.so to add validation i have used following code. I am using reactive forms. in ts file, add following code
根据我的要求，在表单评论框中应该有至少 30 个字符，并且该字符应该是非空格。所以添加验证我使用了以下代码。我正在使用反应形式。在 ts 文件中，添加以下代码
comment:[''[Validators.required,Validators.minLength(30),Validators.pattern(/^((?!\s{2,}).)*$/)]]
Hey this sentence has one space between every word//this will work
Hey this sentence has one space between every word//这会起作用
Hey this sentence has more than one space between every word//this will throw err
Hey this sentence has more than one space between every word//这会抛出错误
I hope this will help somebody in future.
我希望这会在将来对某人有所帮助。
