QT handy notes (II) edit control and float, qstring conversion

1、Edit Control

	QString qstr = ui->lineEdit->text();// Get current Edit Value on , Assign to qstr.
	
	ui->lineEdit->setText(qstr);// Set up Edit The value on is qstr

2、QString Transfer to other types

	QString qstr = “123”;// Definition qstr Value 
	float  valFlo = qstr.toFloat();// take QString  convert to float
	int valInt = qstr.toInt();// take QString  convert to int
	double valDou = qstr.toDouble();// take QString  convert to doublr
	String valStr = qstr.toStdString;// take QString  convert to string

3、 Other types of transfer QString

QString qstr;

float valFlo = 11.1111;
qstr = QString::asprintf("%.2f", value);//float turn QString And keep two decimal places （ Retain x Decimal place , The first is %.xf）