Change attribute values of multiple fields via PyQGIS

Question

I am starting with PyQGIS and I would like to change the values of two fields within selected features:

from qgis.PyQt.QtCore import QVariant
parent = iface.mainWindow()
mc = iface.mapCanvas()
myLyr = mc.currentLayer() #aktueller Layer, der als Quelle genutzt wird
flds =myLyr.fields()
fld1 = "BTYP" #Name of the first field
fld1i = myLyr.fields().indexOf(fld1) #get the index of the first field
fld1val = "herdamit"#Value of the first field
fld2 = "WS"
fld2i = myLyr.fields().indexOf(fld2)
fld2val = "superduber"
caps=myLyr.dataProvider().capabilities() 
myData = {fld1i: fld1val,fld2i: fld2val}
mySel = myLyr.selectedFeatures()
print(myData)
with edit(myLyr):
 if caps & QgsVectorDataProvider.ChangeAttributeValues:
 for f in mySel:
 myLyr.dataProvider().changeAttributeValues({f : myData})
 myLyr.updateFeature(f)

• Joseph: What happens if you run the code, do you receive any errors or does it run and nothing happens? Are you running this from the python console or from a script?
• klaus k.: There is no error and no result. The code is running from the python console

Answer 1

This code-snippet works fine

parent = iface.mainWindow()
mc = iface.mapCanvas()
myLyr = mc.currentLayer()
flds =myLyr.fields()
fld1 = "BTYP" #Name of the first field
#fld1i = myLyr.fields().indexOf(fld1) #get the index of the first field
val1 = "!urmele!"#Value of the first field
fld2 = "E3_KARTO"
#fld2i = myLyr.fields().indexOf(fld2)
val2 = "!durmele!"
caps = myLyr.dataProvider().capabilities()
for f in myLyr.selectedFeatureIds():
 #print(f)
 if caps & QgsVectorDataProvider.ChangeAttributeValues:
 attrs={flds.indexOf(fld1):val1,flds.indexOf(fld2):val2}
 myLyr.dataProvider().changeAttributeValues({ f : attrs })