QLineEdit learning and use

QLineEdit

方法	描述	备注
setText()	设置文本	设置文本,槽函数,不发信号
text()	获取文本
setPlaceholderText()	设置提示文字
setClearButtonEnabled()	Set clear text	Displays a clear button on the right after entering text to clear the input
setReadOnly()	设置只读	distinguish different people（状态时）的权限
setMaxLength()	Set the length of bytes that can be entered	If the input password is the highest8位,Whether it is Chinese or should be based on one digit
setEchoMode()	设置显示模式	setEchoMode(QLineEdit::Normal)

• 掩码格式
  
  

• 信号触发
  
  

• 显示模式
  
  
  
  

• Check out the stylesheet help documentation
  
  

参考代码

//setText()
ui.lineEdit->setText("lineedit test");
ui.label->setText(QString::fromLocal8Bit("邮箱格式不正确！"));

//text()
QString txt = ui.lineEdit->text();
	txt += " ";
	txt += ui.textEdit->text();
	ui.label->setText(txt);

//setPlaceholderText()
ui.lineEdit->setPlaceholderText(QString::fromLocal8Bit("提示输入"));

//掩码输入
	ui.lineEdit->setInputMask("000.000.000.000;_"); //When there is no previous input,用_进行填充;0格式输入：只允许输入数字,但非必须
	//When the user presses the enter key,No matter how many numbers are entered,都会激发returnPressed信号.
	ui.textEdit->setInputMask("AAAAA;_");  //A：只允许输入字母,且必须：必须输入5个字符型数据,才会激发returnPressed信号.

//Enter verification settings
//整数验证
	QIntValidator *ival = new QIntValidator();
	ival->setRange(1, 1000);
	ui.iedit->setValidator(ival); //Set the input valid range,Int整数,范围1-1000.

//浮点数验证
	QDoubleValidator *dval = new QDoubleValidator();
	dval->setRange(-100, 10000,3); //浮点型,范围-100 ~ 10000 ,精度为小数点后3位
	//no scientific notation ：浮点型,Enter complete to verify,So the floating point setting range is invalid..
	dval->setNotation(QDoubleValidator::StandardNotation);
	ui.dedit->setValidator(dval);

//验证邮箱 [email protected]
	QRegExp exp("[a-zA-Z0-9-_][email protected][a-zA-Z0-9-_]+\\.[a-zA-Z]+"); //[a-zA-Z0-9-_]：a-z、A-Z、0-9、-和_都可以匹配.
	//+：Indicates that the preceding character in the range occurs at least once,(*sign indicates that it can appear multiple times,或者不出现)
	// \\. 表示的是\进行转义\\,再加.(由于单独的.is meaningful in regular expressions,therefore need to be escaped),The final result is to display a decimal point.
	QRegExpValidator *rval = new QRegExpValidator(exp);
	ui.email->setValidator(rval);
//Verify that the email is entered correctly
//Incorrect format prompt
	const QValidator *v = ui.email->validator();  //get validation format
	int pos = 0;  //Where the validation error occurred.
	/* 返回 enum State { Invalid, 不正确 Intermediate, 中间状态,End without input：如 [email protected] Acceptable 格式正确 };*/
	if (v->validate(ui.email->text(), pos) != QValidator::Acceptable)
	{
    
		ui.label->setText(QString::fromLocal8Bit("邮箱格式不正确！"));
	}