How do I force the display of a decimal in an ExtJS NumberField to a certain precision?

问题

I have a form with a NumberField that gets values of type float from JSON. If the values happen to be whole numbers, then no decimal places are shown. I would like to show 2 decimal places at all times. Is there a config option for this?

Here's my declaration:

items: [
    { 
        fieldLabel: 'Net Sales',
        name: 'netSales',
        allowBlank:false,
        decimalPrecision:2
    },

回答1:

either extend :

var myNumberField = Ext.extend(Ext.form.NumberField, {
        setValue : function(v){
            v = typeof v == 'number' ? v : String(v).replace(this.decimalSeparator, ".");
            v = isNaN(v) ? '' : String(v).replace(".", this.decimalSeparator);
            //  if you want to ensure that the values being set on the field is also forced to the required number of decimal places.
            // (not extensively tested)
            // v = isNaN(v) ? '' : this.fixPrecision(String(v).replace(".", this.decimalSeparator));
            return Ext.form.NumberField.superclass.setValue.call(this, v);
        },
        fixPrecision : function(value){
            var nan = isNaN(value);
            if(!this.allowDecimals || this.decimalPrecision == -1 || nan || !value){
               return nan ? '' : value;
            }
            return parseFloat(value).toFixed(this.decimalPrecision);
        }
    });

...
...

items: [new myNumberField({
        id  : 'net',
        fieldLabel: 'Net Sales',
        allowBlank:false,
        decimalPrecision:2
    }),

or override, and that will effect all numberfields in your application:

Ext.override(Ext.form.NumberField, {
    setValue : function(v){
            v = typeof v == 'number' ? v : String(v).replace(this.decimalSeparator, ".");
        v = isNaN(v) ? '' : String(v).replace(".", this.decimalSeparator);
        return Ext.form.NumberField.superclass.setValue.call(this, v);
    },
    fixPrecision : function(value){
        var nan = isNaN(value);
        if(!this.allowDecimals || this.decimalPrecision == -1 || nan || !value){
           return nan ? '' : value;
        }
        return parseFloat(value).toFixed(this.decimalPrecision);
    }
})

items: [{
        xtype   : 'numberfield',
        fieldLabel: 'Net Sales',
        allowBlank:false,
        decimalPrecision:2
    },

EDIT

Notice the commented section in the first setValue method.

回答2:

As this was the top result for a search query about forcing decimals in a NumberField, thought I would update this for those using ExtJS 4+

The input filtering since ExtJS 4 has been delegated to a valueToRaw function, the setValue function used is actually from Ext.form.field.Text, so that's what I'm overriding below.

I also decided to have the forcing of displaying decimals to be an option ('forcePrecision') configurable per NumberField, which means the override will look like this:

Ext.override(Ext.form.NumberField, {
    forcePrecision : false,

    valueToRaw: function(value) {
        var me = this,
            decimalSeparator = me.decimalSeparator;
        value = me.parseValue(value);
        value = me.fixPrecision(value);
        value = Ext.isNumber(value) ? value : parseFloat(String(value).replace(decimalSeparator, '.'));
        if (isNaN(value))
        {
          value = '';
        } else {
          value = me.forcePrecision ? value.toFixed(me.decimalPrecision) : parseFloat(value);
          value = String(value).replace(".", decimalSeparator);
        }
        return value;
    }
});

To use this in your form, you'd instantiate it like this:

{
  xtype: 'numberfield',
  name:  'decimalsfield',
  forcePrecision: true,     #defaults to false
  decimalPrecision: 3       #defaults to 2
}

Fields not instantiated with forcePrecision: true behave exactly like the default.

回答3:

The popular solution didn't work for me. In fact the code in the solution is an exact duplicate of the EXT JS 3.3 source code which, for me, displays "1" instead of "1.00" when decimalPrecision is 2. Based on the popular solution's suggestion to override setValue, this is what I did:

Ext.override(Ext.form.NumberField, {
    setValue: function(v) {
        var dp = this.decimalPrecision;
        if (dp < 0 || !this.allowDecimals) {
            dp = 0;
        }
        v = this.fixPrecision(v);
        v = Ext.isNumber(v) ? v : parseFloat(String(v).replace(this.decimalSeparator, "."));
        v = isNaN(v) ? '' : String(v.toFixed(dp)).replace(".", this.decimalSeparator);
        return Ext.form.NumberField.superclass.setValue.call(this, v);
    }
});

Even though the fixPrecision code seems to format the number with the desired precision, javascript would lose the precision during the manipulation it does on the two lines before the call to the superclass's setValue function. Setting the precision with toFixed when it is finally converted to a String made it work.

Good luck!

回答4:

Best bet is probably to add a listener to the blur event for it, and then use the built in Javascript .toFixed(2) function on the value of the field.

回答5:

The option decimalPrecision definition is: "The maximum precision to display after the decimal separator (defaults to 2)"

There is no option to force the format, you problably have to override NumberField class.

回答6:

if you want something like below:

enter 50 > u got 50

50.10 > 50.10

50.123 > 50.12

Try this:

, setValue: function (v) {
      if ( !v || isNaN(v)) {
        v = '';
      }
      else if (v % 1 != 0) {    //means number is not whole number
        v = this.fixPrecision(String(v).replace(".", this.decimalSeparator));
      }

     return Ext.form.NumberField.superclass.setValue.call(this, v);
}
, fixPrecision: function (value) {
    if (!this.allowDecimals || this.decimalPrecision == -1) {
       return value;
    }

    return parseFloat(value).toFixed(this.decimalPrecision);
}

回答7:

This code works great for me. It wont work with out the "ValueToRow" override in ExtJS 4.2.0.

var myNumberField = Ext.extend(Ext.form.NumberField, {
    setValue : function(v){
        v = typeof v == 'number' ? v : String(v).replace(this.decimalSeparator, ".");
        v = isNaN(v) ? '' : String(v).replace(".", this.decimalSeparator);
        return Ext.form.NumberField.superclass.setValue.call(this, v);
    },
    fixPrecision : function(value){
        var nan = isNaN(value);
        if(!this.allowDecimals || this.decimalPrecision == -1 || nan || !value){
        return nan ? '' : value;
        }
        var val = parseFloat(value).toFixed(this.decimalPrecision);
        return val;
    },
    valueToRaw: function(value) {
        var me = this,
        decimalSeparator = me.decimalSeparator;
        value = me.parseValue(value);
        value = me.fixPrecision(value);
        value = Ext.isNumber(value) ? value : parseFloat(String(value).replace(decimalSeparator, '.'));
        value = isNaN(value) ? '' : String(value).replace('.', decimalSeparator);
        return me.fixPrecision(value);
    }
});

...
...
items: [new myNumberField({
        id  : 'net',
        fieldLabel: 'Net Sales',
        allowBlank:false,
        decimalPrecision:2
    })

Reference: How to keep the trailing zeros in Ext.form.field.Number ?

来源：https://stackoverflow.com/questions/1287584/how-do-i-force-the-display-of-a-decimal-in-an-extjs-numberfield-to-a-certain-pre